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Chapter Text

This is a derivative work based on a crossover between the Korean webtoon Villain to Kill (VtK) and Fate/Grand Order (FGO).

Timeline:

VtK takes place after Chapter 183, right before Cassian’s war against the Chinese villain Peony.

FGO is set during the Lostbelt arc .
Fujimaru Ritsuka (female) enters the VtK world—now a Singularity warped by the Holy Grail—alone to retrieve the Grail.

This story contains:

1. Unique lore derived from fusing the worlds of FGO and VtK (e.g., Class Assignments, twisted Holy Grail War rules).

2. Psychological exploration and characterization of Master Fujimaru Ritsuka (female).

3. Original plot and character interactions, including Ritsuka’s contracts, trust-building, and mental resonance with VtK characters.

4. Depictions of characters’ psychological trauma, death memories, and identity conflict.

5. This story is told in fragmented, moment-based episodes, focusing on character growth and emotional resonance.—I'll write whatever comes to mind, whenever I feel like it.

6. No romance or shipping. The central themes are understanding, trust, and resonance between characters.

7. I play the Japanese version of FGO, but I can't read Japanese, so I skipped most of the story… Sorry, I'm really not a hardcore FGO fan,😭
My understanding of Ritsuka Fujimaru is mainly based on the Babylonia anime adaptation, so all FGO-related elements are shaped by my personal interpretation (and imagination). I hope FGO fans won’t mind too much 🙏

8.Contains partial storyline depictions from FGO Ordeal Call: Inescapable Gehenna.

9. VtK serves as the main narrative and tone, with FGO functioning as a support layer.

10. I’ve tried to stay true to character personalities and voices, but due to the merged worldbuilding, there will be some reasonable expansions and introspective scenes.

11.Knowledge of both canons helps, but context will be woven in as the story progresses.

12. The writer’s native language is not English, but every effort was made to maintain tone, clarity, and immersion. Thank you for your understanding and support!

Sorry for the long intro—now let’s begin the actual introduction.

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【Villain to Kill × FGO AU Worldbuilding】

📌 1. Singularity & Holy Grail Setup

The Holy Grail manifests within the VtK universe, distorting its structure and transforming it into a Singularity.

Both Villains and Psykers are assigned Servant-like Classes and spiritual data, essentially turning them into Servant-equivalents with “Spirit Origins.”

A twisted version of the Holy Grail War begins unfolding within this altered VtK world.

All residents within the region are affected by the Grail. They undergo changes and receive fragmented knowledge about “Servants,” “Masters,” and “the Grail.”

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📌 2. World Integration Principles

Original elements of VtK are not erased. The Grail’s distortion serves as a lore bridge that makes VtK compatible with the FGO system.

Fujimaru Ritsuka, as an "outsider," is not recorded by the VtK world’s logic system. Her magical tools and systems (e.g., Mystic Code, Summoning Ability, Master Contracts) attract the attention of all major factions.

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📌 3. Mana & Magecraft Fusion

The Grail’s interference gives rise to new Leylines across the VtK world, enriching the air with mana.
Ritsuka is able to restore her magical reserves through her Mystic Code and the ambient mana.

The Mystic Code is modified by Da Vinci to provide stable mana flow, healing, and defense support.

Villains can replenish mana using Magic Stones, but the cost is steep, often leading to mental collapse or berserk awakenings.

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📌 4. Contract & Summoning System

Full-fledged Servant summoning is not possible within this Singularity. Fujimaru Ritsuka can only summon "Shadows of Spirit Origins"—combat projections modeled after Servants.

Chaldea is unable to send physical Servants, but can still provide remote support, translation, and tactical data.

When a Master-Servant contract is formed, a spiritual bond is created—allowing for shared dreams and partial memory resonance.

Cassian, transformed by the Grail into an Avenger-class Servant, forms a contract with Ritsuka.

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🔷 Character Profiles

Fujimaru Ritsuka (Female)

The only Master in the Singularity and a true outsider to the VtK system.

Unable to summon full Servants; can only summon “Spirit Origin Shadows” for temporary battle support.

Wears a modern Mystic Code designed by Chaldea resembling casual or school attire to blend into city life.

Has no companion Servant, but receives real-time support via Chaldea’s communication network.

Language translation is provided via Chaldea tech—instant and seamless.

Takes on the alias “Orange Mask” and joins the “Gadam Vilzone”, living and cooperating with local Villains in the Heaven Bar.

Eventually forms a contract with Cassian and begins joint operations.

Fou

a creature that was supposed to remain in Chaldea, yet somehow accompanied Ritsuka during the Rayshift.

Although its intelligence remains diminished, it always perks up its ears and lets out a low cry whenever danger draws near, as if it can sense the killing intent approaching.

For the solitary Ritsuka, this little beast is the most reliable guardian of all.

Cassian (Avenger)

Once a top-class Psyker under Lampas, betrayed and hunted to death.
Resurrected by Moros at great cost and now the Boss of the Gadam Vilzone.

Wields dark-blue flames, shadow chains, and multiple blade forms.
Gains a mental link with Ritsuka upon contract.

Moros

A floating eye-like spiritual being calling itself a "noble ancient soul."

Bound to the necklace worn by Cassian. Only the wearer can perceive it directly.

Due to being spiritually tied to Cassian’s Spirit Origin, Ritsuka becomes aware of Moros’s existence.

Possesses the skill “Color Eye”, allowing it to analyze stats and attributes—but Ritsuka’s data appears vague or glitched.

Driver (Caster)

Former Gadam Vilzone Boss and mechanical engineer.

Gentle, brilliant, and strategic—acts as a tactician and gadget supplier for the Villain Zone.

Excels in tech-based Magecraft and device construction: masks, drones, comms, etc.

Has Caster Class with Archer and Lancer aptitude.

Uses floating turret-type Noble Phantasms for long-range support.

Very curious about Ritsuka’s origins and Mystic Code.

👁 Factions and Conflict:

The Four Fiends, elite assassins under Peony (a powerful Chinese villain), secretly enter Seoul before the Singularity sealed the city.

Cassian, Driver, and other Villains must protect Gadam Villzone from these invaders.

Chaldea Support Team

Includes Da Vinci, Mash, and others who provide remote comms, analysis, and data.

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🔥 Contract Mechanics (VtK × FGO Holy Grail Distortion)

A. Servant-Type Villains

Mana Source:

Normally rely on Magic Stones—rare and costly.

Overuse leads to madness, loss of control, or berserk awakenings.

Awakening System:

Grow stronger through powerful emotions and inner desires.

Each stage (First, Second, Third Awakening) comes with increased power but fragile sanity.

Effects of Master Contract:

1. Stabilizes mental state post-awakening.

2. Grants clean, stable mana—removing reliance on Magic Stones.

3. Provides psychological grounding, preventing emotional collapse.

4. Allows them to retain rationality and humanity despite being Villains.

B. Servant-Type Psykers

Mana Source:

Naturally developed mana circuits through Lampas training.

Power Development:

Abilities are enhanced via physical/mental training and compound skill systems.

Effects of Master Contract:

1. Unlocks hidden skills or Class traits.

2. Increases mana efficiency and reduces skill cooldowns.

3. Enables temporary power bursts under pressure.

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💡 The Holy Grail’s Twisted Influence

Villains and Psykers were not originally part of the Holy Grail War system. However, the Grail’s distortion restructured reality, granting them Spirit Origins and Class Attributes akin to Servants.

They did not require Masters in their original form, but the Grail’s expanding rules forced a “Master Compatibility” adaptation into their existence.

This makes Fujimaru Ritsuka the only true Master in this world—naturally becoming the war’s catalyst and core anomaly.

---

Thank you for reading and supporting this wild crossover idea!
Feel free to ask me questions or share your thoughts—I’m always happy to talk about it! 💬

Chapter Text

Night had fallen over Seoul, yet the streets remained brightly lit. Pedestrians hurried along the sidewalks, the roar of car engines mingling with the colorful glow of neon signs, carried on the slightly humid early-summer breeze.

Suddenly, an unknown beam of intense light poured down from the sky, instantly covering the entirety of South Korea.

No warning. No sound. The light was unlike sunlight; it penetrated buildings, stretched across streets, and shone upon everyone indiscriminately.

At that moment, Cassian had just finished training and was standing alone atop a high balcony in the Gadam Vilzone , enjoying the evening breeze.

“Cassian, are you okay?!” Moros’s voice sounded beside him, tinged with barely concealed anxiety.

“Ugh…” Cassian suddenly clutched his head—not with an ordinary headache, but as if some scorching force were forcibly etching itself into his mind. Strange information surged ceaselessly in his brain. He felt his body undergoing bizarre changes under the mysterious light. An uncontrollable rage burned in his chest, his hatred toward Lampus and desire for destruction swelling dangerously high, as if reason might snap at any moment. Clenching his teeth, he tried to suppress these emotions, but waves of pain threatened to overwhelm him.

“What is going on? And what the hell is this Holy Grail?” Cassian struggled to restrain the destructive urges before he could focus on processing the flood of information in his mind—information far beyond his previous comprehension.

“…I don’t know. I’ve never heard of a Holy Grail before. But I’m certain the abnormal phenomena just now were caused by it. Let’s check your status with the Color Eye.” Moros sounded perplexed; even this ancient, knowledgeable entity had never encountered anything like the Grail.

“You don’t know either? Aren’t you always claiming to be a noble soul from antiquity? And yet there’s something you don’t know?” Cassian muttered while forcing himself upright, checking the information display. He froze when he saw a new entry under Special Notes: [Servant – Class: Avenger].

“Avenger? That damn light turned me into a Servant? Could it have affected the others too…?”

Beep beep! Cassian’s phone buzzed. It was Driver, summoning him immediately to an emergency meeting.

The conference room in the Gadam Vilzone was already filled.

“Everyone here? Are you physically okay?” Driver asked the assembled villains.

“Completely fine~ 🖤!” Crow chirped, full of energy.

“My head hurt when all that knowledge about the Holy Grail War flooded in—I thought I was growing a second brain for a moment.”

“What’s happening now? We’re not seriously having a Grail War, are we?”

“Yay! Fighting time!”

“Shut your mouth!”

“Ow!”

The villains seemed more hyped than ever, as if on some stimulant. Amid the chaos, Cassian spoke coldly:

 “Quiet. Our war with Peony is already enough trouble, and now there is the Holy Grail… Driver, can you confirm its location? Heaven's Flower will undoubtedly covet it as well. We can’t let them get it. Nor Lampus.”

“My thoughts align with the Boss’s. We cannot let the Grail fall into Heaven's Flower’s hands. The Psykers probably received Class Attributes like us. If Lampus gets the Grail, they’ll clamp down on villains even harder. If necessary, we strike first.” Driver was unusually serious. “I’ve reviewed the drone footage. The strange light likely caused intermittent signals, misaligned visuals, and delays. I’ll upgrade the drones and the security system soon. The vigilance of the Vilzone is up to you all.”

At the Cheonhyang Flower Garden headquarters, Vice-Director Tang Yan sipped her tea, the aroma curling gently.

“Interesting. The all-powerful wish machine—the Holy Grail—will surely aid the Leader’s grand ambitions,” she said, lightly smiling, her fingertips tracing the rim of her teacup.

“It seems the script needs rewriting,” Tang Yan murmured, setting down the cup after a delicate sip, her gaze dark and deep.

At Lampus Korea, a press conference was held immediately to reassure the public, followed by an emergency internal meeting.

“We still can’t reach Headquarters?” Lampus Korea Branch Chief Ma Guanghao frowned, impatiently tapping the table.

“Never mind. Peony likely can’t contact their subordinates either. That might actually be a good thing,” he said coldly, smiling faintly. “One of the Four Perils, Qiong Qi., is dead. We have six top-tier Psykers; that’s enough to handle the remaining three Perils and the Cheonhyang Flower Garden Vice-Director. Eliminating them will severely weaken Cheonhyang Flower Garden and give us an advantage in future operations against Peony.”

Chaldea, Control Room.

Piercing alarms echoed throughout the control room, red warning lights flashing incessantly. The displays showed chaotic information streams: mana concentration spiking, spatial structures warping.

“Detected large-scale Human Order anomaly!”

 “Singular Point formation observed, encompassing the entirety of South Korea, in the modern era.”

Little Da Vinci furrowed her brow, her expression serious:

 “This Singular Point repels Servant Spirit Cores. We cannot deploy any Servants.”

“Only Ritsuka can enter the Singular Point to repair it. Chaldea will provide remote support. Be extremely careful.”

“Understood. Recovering the Grail is up to me.” Fujimaru Ritsuka, the last remaining human Master, stepped forward, her gaze fixed on the map, now shrouded in black light.

“I regret not being able to accompany you inside. I’ll do my best to support from the perimeter. Please take care,” Mash’s voice said, tinged with concern.

With full preparations made, Fujimaru Ritsuka initiated Spirit Transfer.

Ritsuka opened her eyes to find herself standing on an unfamiliar modern street. To avoid drawing attention, she wore a Chaldea-provided casual-style magecraft outfit, appearing like an ordinary student or civilian while still facilitating movement. She exhaled slowly, activating the communicator on her wrist to contact Chaldea.

“Fujimaru Ritsuka has successfully arrived at the Singular Point.”

“Received. Ritsuka, you are now in Seoul, South Korea,” Little Da Vinci’s voice came through. “Mana concentration here is low. Prioritize intelligence gathering and proceed cautiously.”

“Understood. I’ll be careful.” Ritsuka nodded, scanning her surroundings. The streets were bustling; cafés glowed warmly, people chatting, taking photos, or walking leisurely. The city seemed oddly peaceful, with no abnormal mana waves—as if this Singular Point were an extension of everyday life.

“The calmer the surface, the greater the caution required,” Ritsuka thought, moving discreetly along the streets, eyes alert.

She reached a busy intersection, intending to observe the terrain from a wall, when a sudden, violent explosion shattered the city’s tranquility. A convenience store’s wall was blown halfway off, screams and breaking glass mingling with a chilling laughter.

“—!” Ritsuka pivoted immediately, locking her gaze on the rising smoke.

“Spirit Core detected ahead! Mana signature matches Servant system at 82%, not from generic human history. Classified as pseudo-Servant-level entity.” Little Da Vinci and Mash’s voices came through the communicator.

“These entities are ‘pseudo-Servant lifeforms’ affected by the Grail. Originally residents of this Singular Point, now granted Spirit Core attributes. Exercise extreme caution!”

“Ahahaha—ahahahaha! Now this is fun—!” The smell of gunpowder and laughter mingled as a  oddly dressed, heavily made-up men emerged from the smoke. His grins stretched unnaturally, eyes blood-red, expressions manic. Around him, five identical clones attacked nearby pedestrians recklessly.

This was no ordinary act of violence. Instinctively, Ritsuka summoned her Spirit Shadow, her only combat resource in this mission.

At that moment, a young man dashed from a street corner. He wore a simple plain-colored Sweatshirt and dark jeans, appearing to be an ordinary civilian—but in the next instant, he leapt forward, striking with precision and knocking the aggressors back. His movements were agile and controlled, as if a skilled martial artist, his strikes perfectly restraining the attackers.

Ritsuka was slightly surprised by his reflexes and judgment, but adjusted her pace to coordinate. With synchronized movements, they quickly subdued the assailants.

In the brief calm, Ritsuka’s attention was drawn to a strange anomaly—just behind the young man’s shoulder, something seemed to tremble slightly in the air.

Squinting, she saw a faint, floating blue figure… vague, yet enough to make her scalp tingle.

—A floating black eye.

“…What…?” Ritsuka whispered, instinctively rubbing her eyes before staring again.

In the next moment, she could sense the “eye” was observing her as well.

The young man, after a half-second pause, barely raised an eyebrow.

“…Thank you for your help.” Ritsuka nodded politely. Thanks to the translator charm made by Little Da Vinci, her words automatically converted to his language.

“I’m just an ordinary passerby. Be careful; this area hasn’t been safe lately,” he said, nodding once before turning and leaving.

Ritsuka stood still, frowning as she watched his retreating figure. The image of that floating “eye” lingered uncomfortably in her mind.

Chapter Text

After leaving the scene, Cassian walked through the streets and slipped into an alleyway. Once he confirmed no one was around, he stopped.

“…You noticed it too, didn’t you?” Cassian spoke in a low tone.

“That girl… she isn’t an ordinary human. She could see me, stared at me for several seconds… even rubbed her eyes, like she was trying to confirm something.” Moros’s voice echoed faintly, tinged with surprise.

“Not only that, her ability is unusual. A Psyker, perhaps?” Their brief cooperation in battle had already caught Cassian’s attention: the girl could summon powerful afterimages, maintain composure amidst chaos, react instantly, and provide precise support after reading her ally’s intentions. Such skill was exceptional even among Psykers—and her presence carried the weight of countless battles.

“Not sure. But… she looks like one.” Moros lowered his gaze as if in thought. “The process she used to summon those afterimages was… complicated.”

“Use your Color Eye. Pull up her data.” Cassian’s voice was firm.

“Understood.” Moros obeyed without hesitation. In the next instant, a translucent pale-blue status window flickered into view, visible only to him and Cassian.

But the data was obscured: values scrambled, class unknown, attributes unknown, magical energy a string of garbled codes.

“What the—? Nothing’s clear. Is your Color Eye malfunctioning?” Cassian frowned, gaze narrowing at the display.

Moros’s voice grew uncharacteristically grave. “It’s not that my ability failed. It’s that… her existence doesn’t belong to this system. There’s only one explanation.”

“You’re saying… she doesn’t belong to this world?”

“That’s the only reasonable conclusion. She may be an anomaly summoned by the Grail.”

Before Cassian could press further, his phone buzzed.

A message from Dreibor: the villain who had attacked earlier wasn’t working alone. Drones had detected his partner lying in wait nearby, preparing for a retaliatory strike.

Cassian’s eyes hardened. In the next moment, he transformed into his Villain form and slipped into the shadows, racing back toward the district.

---

The street was slowly settling back into calm. Police sirens wailed faintly in the distance. Crowds that had gathered were dispersing, as if nothing had ever happened.

Fujimaru Ritsuka exhaled softly. Perhaps due to the Singularity’s interference, her magical energy was recovering painfully slowly.

“…I need to find a quiet place to rest.” She murmured to herself, moving to lean against the wall of a nearby shop. Taking a deep breath, she activated her communicator.

“This is Fujimaru Ritsuka. With the help of local residents, I’ve successfully defeated a pseudo-Servant-class opponent. Its power didn’t stem from magecraft—it was more like a psychic superpower. I’ll continue to observe further.”

Da Vinci’s reply came swiftly: “Understood. It seems this Singularity’s structure is very different from the norm. It lacks typical ‘Mystery’ concepts. Your judgment is sound. Prioritize your safety, then gather more intel. And remember—if another Servant-class enemy appears, report it immediately.”

“Got it.” Just as Ritsuka was about to close comms, a sharp crash—the sound of shattering glass—rang in her ears.

She instincts twisted aside just in time. A flash of orange-red fire erupted from the alley ahead. The shockwave sent her sprawling to the ground, her ears ringing.

“Well, well… aren’t you a tough little miss? Beating down my partner like that…” A figure emerged from the smoke, mouth twisted in a manic grin. Half his face was hidden behind a shattered respirator, his hair wild like flames.

“…!” Ritsuka bit back the pain of the blast, immediately summoning a Spirit Shadow. But her magical energy was still low—her full combat time was limited.

“Come on! Scream! Cry!” The villain laughed, hurling a glowing blue vial.

It shattered at her feet—stone pillars burst from the ground. She leapt back reflexively, forced deeper into the narrow alley. The air grew thick, charged like a fuse ready to ignite.

More vials exploded one after another, smoke and ruptured earth pressing her down. She was being completely overwhelmed.

And then—

“—BOOM!!!”

A torrent of black-and-blue flame sliced through the haze like a falling star. From the shadows, a figure burst forth, his fist slamming the villain into the ground.

Through the smoke, his mismatched eyes—one burning gold, the other cold blue—glimmered sharply.

“You’re hurt.” His voice was low, gaze flicking to her injured shoulder and knee. “Find somewhere safe and hide. Don’t push yourself.”

Ritsuka froze for a moment, then nodded. “…All right. I’ll leave it to you.” She slipped down a side passage, hiding behind a nearby house’s blind spot, and quickly reopened comms.

Cassian gave the faintest nod before turning back to face the villain—already standing, laughing wildly through the blood on his lips.

---

Ritsuka hid herself in the shadows of a street corner, carefully checking her Mystic Code for damage and her current state of magical energy. Luckily, none of her wounds were too severe; after activating the built-in healing magecraft of the Code, the bleeding had already stopped.

Her gaze fixed on the battle ahead. The moment that man with heterochromatic eyes appeared, she couldn’t help but hold her breath. His movements were swift and relentless, every strike carrying overwhelming force—an unmistakable display of combat prowess far beyond that of any ordinary human.

“This is Fujimaru Ritsuka. I was just attacked again, but a pseudo-Servant-class individual intervened to protect me. He is now engaging the enemy. I’ve retreated to a safe location and will provide support from range.”

“Copy that. Your vitals show slight fluctuations. Avoid any high-intensity combat for now.”

Ritsuka drew in a deep breath, steadying her heart before fixing her eyes once more on the battlefield where fire and smoke collided. The figure standing tall amidst the chaos—chains as black as shadow, blades erupting like projections, and finally, hellfire that devoured the enemy whole. The sight brought to mind certain Servants she knew all too well.

---

Dark blue flames roared amidst the haze, shockwaves ripping outward.

Cassian leapt high, crashing down with glowing eyes—one golden, one azure—like a beast awakened.

The villain stood in the center of the street, grinning manically, thrilled.

“Come on! Let’s see if you can withstand my Explosive Inferno! Hahaha!” He spread his arms, the air trembling as visible shockwaves burst from his body.

Cassian snorted. He dashed forward in an instant, leaving afterimages.

—CRACK!!

His fist smashed into the villain’s jaw, sending him flying into a metal signpost. Before the villain could recover, shadows surged, binding his limbs.

From above, Cassian appeared, flames of abyssal blue igniting in his hand.

“Hell fire!” He thrust it down—melting asphalt and walls alike.

The villain barely rolled aside, but his left arm was charred black, smoking from the burn. He laughed madly, tearing through the restraints.

“HAHAHA! Yes! You really excite me! Come on—AGAIN, AGAIN!!”

Slamming his hands to the ground, a ring-shaped shockwave erupted, stone spires exploding upward.

Cassian’s eyes narrowed. He flung a barrage of shadow blades, pinning the villain’s legs.

“…Finished talking?” He sank his stance, driving forward with a flurry of crushing blows.

BAM—BAM—BAM! Each strike landed hard and precise, brutal but controlled. The villain was pummeled into the pavement, helpless.

Before the final punch, Cassian muttered low: “You shouldn’t have caused trouble in Gadam.”

BOOM!

The street fell silent. Only the crackle of flames remained.

Among the rubble, the villain lay half-buried, unconscious, his crazed grin gone.

“She shouldn’t be far…” Cassian brushed dust from his jacket, turning to sprint toward the direction Ritsuka had fled.

Chapter Text

Villain from Chapter 1: Grin-Ape

Rank: C+

Class: Berserker

Appearance (after transformation):

His face is painted with exaggerated clown-like makeup: one side a wide, torn grin, the other marked with ripped crimson lines. A broken monkey mask hangs crookedly on the side of his head.

His upper body is bare, covered in crimson tattoos and scars, with metal orb-like ornaments on his shoulders and elbows.

He wears ragged camouflage pants and heavy combat boots. His attacks are often accompanied by deranged, manic laughter.

Abilities:

1. Phantom Split

Creates 3–5 “laughing afterimage clones” with grotesque grins. These illusions mimic his movements and laughter, confusing the enemy’s judgment.

The clones have no attack power and vanish when struck, but combined with his wild movements, they create intense pressure. → They don’t deal damage, only disorient, making opponents feel surrounded.

2. Ape Tricks

Pulls out a collection of “gorilla-style clown weapons,” such as:

Fake grenades (actually filled with tear gas).

A switchblade (that suddenly extends with a loud snap).

A lighter that spews an unexpectedly large flame.

A blaring horn (deafeningly loud).

A ribbon bomb (erupts with metallic shards instead of confetti).

These props create chaos and small-scale destruction, despite their clownish appearance. His exaggerated acrobatics make him look like a clown performing tricks, but they are deadly distractions.

Combat Style:

Entrance: Always appears with a grotesque “Hahahahaha—!” while his clones scatter.

Attack: Combines clones and props, making it hard to tell what’s real.

Psychological Warfare: He enjoys making his enemies feel fear + disgust + confusion, more than simply defeating them.

Personality: A pure sadist who finds pleasure in suffering and destruction. Loves to provoke and toy with prey, savoring their despair.

Catchphrases:

“Heeey~ how long can you last? Scream for me, c’mon—Hahaha!”

“Ohohohoho! Let’s dance, little monkeys—!”

“Can’t tell, can you? Which one’s real? Which one’s gonna smash your face? Hahaha!”

---

Villain from Chapter 2: Crackbomb

(Name inspired by his ability to crack the ground and trigger explosions)

Rank: A

Class: Berserker

Appearance (after transformation):

Half of his face is covered by a shattered respirator, from which irregular laughter and gasping breaths can be heard.

His hair is wild, dyed in a black-to-orange gradient, curling upward like flames.

He wears a battle coat made from an oil-stained lab uniform, painted with hand-drawn skulls and explosion symbols.

Around his waist hang several homemade elemental vials, ready to ignite and alter the battlefield.

Abilities: Earth-element manipulation (Seismic and Petrification)

Can split the ground, raise stone pillars, and reshape terrain to trap or block opponents.

Creates smoke or poisonous gas to obscure vision and disrupt breathing.

Personality:

Revels in controlling space and forcing prey into inescapable explosions.

Cackles like a madman while counting down, savoring the terror of those with no way out.

Often mutters deranged lines like: “Can you smell it? That’s the air right before an explosion.”

Additional Notes:

1. Skilled in ambushes and trap-setting.

2. Close friends with Grin-Ape; the two often wreak havoc together.

3. The Holy Grail’s influence has made him more aggressive and battle-hungry.

Chapter Text

Night had fallen, and the streets glimmered faintly under scattered neon lights.

A shadow darted swiftly through the alley, movements agile and precise. In the darkness, his heterochromatic eyes—one golden yellow, the other icy blue—flashed with a cold, dangerous gleam.

He came to a halt, gaze fixed on the figure not far ahead.

“Are you alright?” he asked.

Fujimaru Ritsuka turned toward him, meeting those mismatched eyes. The moment she noticed the floating black eyeball hovering at his side, she realized he was the same young man who had fought alongside her earlier against the terrorists.

“You’re… no, I’m fine. Thank you for saving me,” she said quickly, deciding now wasn’t the time to expose his identity.

Cassian gave a small nod, as though having made up his mind.

“I’m Cassian. There have been a lot of terrorist attacks in this area lately. It’s dangerous to move around alone. If you’re willing, I can take you somewhere safer—where my companions are.”

“…Alright. I’ll go with you.” Ritsuka agreed, recalling the ambush she had just barely escaped. The situation in this Singularity was far more complicated than she’d expected. She needed more information.

“Before we head out, put this on. It’ll help hide your identity.” Cassian pulled out an orange mask—resembling those from a tokusatsu squad—and handed it to her. (One of Driver’s works.)

“You still have the same taste as ever. At this rate, you’ll have a full fake sentai team,” Moros snorted.

“…?” Ritsuka didn’t understand, but obediently put on the mask anyway.

---

In the night air, Cassian princess carried Ritsuka  through several back alleys, away from the bustling streets, until they reached a zone filled with abandoned buildings. At last, they stopped in front of a building with a flickering neon sign that read Heaven Pub.

“This way. Have something to drink, rest a little. The grapefruit soda here isn’t bad,” Cassian said as he set Ritsuka down and pushed the door open.

Behind the bar stood a man in a luxurious fur coat, his pastel-pink hair fading into blue at the tips—Chaeha Yu, the owner. Beside him was a bald man in sunglasses and a suit, polishing plates with silent efficiency.

“Two grapefruit sodas. And a sandwich. Also, I’ll need the med kit,” Cassian ordered.

Ritsuka glanced around cautiously before sitting beside him. Though the sign said pub, there was surprisingly little smell of alcohol. The air was lively, yet carried an inexplicable weight.

Chaeha Yu cast them a brief glance. “…A new face,” he murmured, but asked nothing more. With practiced motions, he placed ice cubes into two crystal-clear glasses, poured in his homemade grapefruit syrup and sparkling water, and stirred gently. A thin slice of fresh grapefruit garnished each rim, the pale orange liquid glowing softly under the lights.

Cassian accepted the drinks silently, passing one to Ritsuka. She removed her mask at his signal and took a sip. The cool, fizzy sweetness eased her nerves. “It’s good,” she admitted.

Soon after, a girl in a maid-style uniform appeared, silver hair flowing with a faint pink gradient at the ends. She carried a tray in one hand and a med kit in the other, a bright, practiced smile on her face.

“Here’s your sandwich~” she chimed, setting both items on the table. Her voice was gentle and polite, yet her smile felt strangely rehearsed.

“Thank you,” Ritsuka replied reflexively.

The girl tilted her head, studying her. “First time meeting you. I’m Song Ha-yeon, staff here. Welcome to Heaven Pub~” Her cheerfulness was natural and disarming, as if she truly were just an ordinary girl.

“You know how to treat wounds yourself?” Cassian asked, nodding toward the med kit.

Ritsuka nodded and began tending to her injuries.

The door opened again with a soft creak. Light footsteps entered—a short stature young man with a brown ponytail and violet-lensed goggles, fiddling with a purple screwdriver in his hand. He looked around with curiosity before spotting Ritsuka. The lenses of his goggles lit up faintly, reflecting a glow.

“A newcomer? Nice to meet you, I’m Driver.” He introduced himself warmly, sitting beside Cassian. His gaze shifted to Ritsuka, and the glow of his goggles flickered like a scanning device.

"She was a passerby who was caught up in the situation when I was subduing the troublemakers. She was slightly injured, so I brought her here for some simple treatment." Cassian briefly explained the origins of Fujimaru Ritsuka.

“…Interesting.” Driver pushed his goggles up slightly, leaning forward to examine her. There was no hostility in his expression, only curiosity. “Your gear is unusual—like nothing I’ve seen before.”

Though Ritsuka sensed no malice, she still gripped her glass tighter. The chilled soda steadied her nerves. “…Hello, I’m Fujimaru Ritsuka.”

At her name, Cassian and Driver both raised an eyebrow.

“…Japanese?”

“The tech behind your gear isn’t Japanese at all. The design looks custom, with a unique structural system. Can you explain its function?” Driver’s goggles shimmered with a faint blue light as he examined the fabric. His tone was earnest, like an engineer geeking out over an invention.

Ritsuka hesitated, touching her sleeve. “…It was made by the organization I belong to, designed for operations in hazardous environments. It offers some impact resistance and mobility enhancements.”

“…A hybrid of multiple systems. Fascinating. With some tweaks to the power feed and material layering, you could cut the energy cost in half,” Driver murmured, almost to himself.

His calm, objective tone lowered her guard slightly.

“You still get excited over new things,” Cassian muttered.

“I’m just saying,” Driver grinned, then added to Ritsuka, “If you ever feel like talking about the design, I could help optimize it—free of charge.”

“I don’t mean harm,” Ritsuka raised her hands. “I came to investigate the abnormality affecting this region. If you’ve noticed any strange energy surges or disturbances, I’d like to hear them.”

Cassian and Driver exchanged a look. “…If you’re willing to cooperate, we can share what we know. Things have indeed gotten unstable—more than just random terrorist attacks.”

“About three days ago, a mysterious light blanketed all of Korea,” Cassian explained. “Ordinary people were unaffected. But those like us—superpowered—were suddenly given extra attributes and knowledge of something called a ‘Holy Grail War.’ Psykers, the ‘children of daylight,’ are fine. But villains—the ‘children of night’—whose powers stem from emotion, lost control more easily. That’s why you’ve seen random outbursts.”

“…The Grail.” Ritsuka’s eyes widened. She steadied her breath and spoke gravely. “That explains it. The Holy Grail is a mass of pure, concentrated mana that twists human history. It grants wishes, yes—but by overwriting the natural order. Left unchecked, it will collapse Human Order itself. And when Human Order falls, humanity perishes.”

“I know this is hard to believe, but it’s the truth. I’m from Finis Chaldea—the Organization for the Preservation of Human Order. We detect distortions in history, called Singularities, and use Rayshift technology to enter and restore them,” she revealed.

The pub fell silent. Cassian, Driver, and even Chaeha Yu and the bald man behind the counter looked stunned.

“…So this anomaly could end the world.” Driver twirled his screwdriver slowly.

“She’s telling the truth,” Moros said softly to Cassian. “The Grail isn’t a gift—it’s a tumor. A disaster core, rewriting existence itself.”

“Eliminate the impossible, and whatever remains, no matter how strange, must be the truth,” Cassian muttered. “Your information defies our logic, but it explains everything. The Grail is dangerous, and we won’t let it fall into enemy hands. In that case, our goals align. For now, you’ll be known here as ‘Orange Mask.’ If you need help, use the comms built into it.”

“Thank you! And if you need help, I’ll do my best. I’m Chaldea’s last Master. I can’t summon Servants here, but I can call forth shadows of their power.” She lifted her right hand, the Command Seals glowing faintly. “These are Command Spells. I can only use them three times, but each is a crystallization of magic strong enough to trigger a Noble Phantasm.”

“…That aside, where do we put her up? She can’t exactly sleep on a park bench,” Cassian asked, turning to Chaeha Yu.

“This is a bar, not a shelter—”

“I’ll cover the cost.” Cassian’s tone was firm, brooking no refusal.

“…If she lets me study that gear, I’ll split the fee,” Driver added with a grin.

“I could work here, to cover expenses,” Ritsuka offered softly.

Chaeha Yu sighed, tossing her a key. “…Second floor, big room. Just cleaned. Be here tomorrow to help out.”

“…Thank you,” Ritsuka whispered, clutching the key. For the first time since arriving, warmth filled her chest. Tonight, at least, she had a place to rest.

---

The door to the second floor room of Heaven Pub creaked open. Ritsuka Fujimaru stepped into the tidy space—her only place of respite within this strange and perilous city.

She activated her communicator. At once, the projection screens lit up with Da Vinci, Mash, and several staff members from Chaldea’s technical division.

“This is Fujimaru Ritsuka. After exchanging information with local residents of the Singularity, I’ve confirmed the anomaly began three days ago. The Holy Grail has twisted this world into a Singularity, transforming local superhumans into beings comparable to Servants. Under the Grail’s influence, they also gained knowledge related to the Holy Grail War—just like summoned Servants do upon materialization.

These superhumans are split into two categories: the Children of Daylight—Psykers, whose stability remains relatively high; and the Children of Night—Villains, who draw power from emotions and desires, and are now prone to losing control. They don’t appear to have the awareness of being ‘Servants’; rather, they process these changes according to their own understanding. Ordinary people, meanwhile, have no awareness of the Grail’s presence at all.”

Da Vinci took notes rapidly, nodding.

“According to the combat data you just transmitted, the energy signatures of the three pseudo-Servant-class individuals you encountered show strong similarities. The two who attacked you were both classified as Berserkers. The one who aided you shows significant energy output, and his classification is Avenger.

We’re also analyzing mana diffusion and spiritron stability rates. If that Avenger is willing to cooperate, it may be possible to establish a contract-like support system here. But unlike your previous Servants, he was not summoned—his very existence has been rewritten by the Grail’s distortion. You’ll need to be cautious. Whether his rationality can remain stable is still uncertain. Remember—your safety comes first.”

Ritsuka clenched her fist.

“Understood. If both Villains and Psykers wield Noble Phantasm-level destructive power, this war could devastate the entire city. I’ll continue reconnaissance while keeping a low profile. If necessary, I’ll intervene in this so-called ‘Holy Grail War.’”

Mash’s voice trembled with guilt.

“I’m sorry… If only I could enter the Singularity with Senpai, you wouldn’t have been hurt.”

Da Vinci quickly reassured her.

“You’ve already been invaluable, Mash. Even if you can’t deploy directly, you’ve been providing communications, data analysis, and mana flow monitoring. You haven’t missed a single role, you know?”

Ritsuka added warmly, “That’s right. It’s thanks to your support that I can explore this Singularity with confidence. Don’t blame yourself too much. This is the only way we can fight side by side right now.”

Encouraged by their words, Mash straightened.

“…Yes. Then I’ll continue assisting Da Vinci-chan to gather intel and help Senpai make tactical decisions for the next move.”

“Thanks, Mash,” Ritsuka replied softly.

Sensing the mood lighten, Da Vinci shifted the subject with a grin.

“By the way, I’m quite intrigued by that engineer friend of yours. If I ever get the chance, I’d love to chat with him. His modification proposals sound promising. Once you return, I’ll get started on improving your Mystic Code.”

…

At the edge of the screen, static crackled as the signal wavered. Ritsuka turned to the window, gazing out over the neon-lit skyline of Gadam District. Quietly, she began plotting her next move.

Chapter Text

Cassian sat on the edge of a high balcony in the Vilzone, a still-unopened metal cola in his hand. Moros floated quietly at his side.

Cassian muttered under his breath, “So the Holy Grail is really a source of magical energy powerful enough to twist reality itself… sounds no different from a magic stone.”

Moros replied, “You sound disappointed. If the Grail truly could grant you a wish… what would you do?”

Cassian didn’t answer right away. He set the metal bottle down and stared at his hands, his fists tightening slightly. “I’ve… thought about it before,” he said in a low voice, rare emotion slipping into his tone.

“Ever since I relived. If only none of this had happened—Jeff wouldn’t have died, I wouldn’t have died, and I wouldn’t have stolen the life of some boy named Kwon Kangwoo—”

Moros simply watched him in silence, offering neither interruption nor response.

Cassian slowly raised his head, gaze fixed on the endless darkness stretching across the sky.

“…But what’s done is done. I won’t wish on the Grail. Even if it could give me a new world, it wouldn’t erase the blood on my hands.” His voice was quiet, yet unwavering, as he turned to meet Moros’s gaze.

The night wind swept past once more. He and Moros sat there together, wordless.

---

The next morning, Cassian pushed open a side door and stepped into Driver’s workshop.

Without looking up, Driver returned his screwdriver to the rack, as though already knowing who had arrived.

Cassian’s tone was heavy. “You finished investigating her background?”

Driver nodded, eyes gleaming with clinical sharpness. “I did. I combed through Japan’s civil registry database—old records, hidden backups, all of it. There’s no such person as ‘Fujimaru Ritsuka.’ No birth record, no school records, no medical history, no residency data. Nothing.”

Cassian was silent for several seconds.

“And that ‘organization’ she mentioned… I cross-referenced the keywords she described with international intelligence networks, both civilian and military registries. There’s nothing. She’s not blacklisted, not tied to any underground group. It’s like—”

“She doesn’t exist,” Cassian finished quietly.

Driver inclined his head, voice calm but tinged with analytical fervor. “She’s like a meteor. Something that never belonged to this sky, suddenly streaking across it, leaving a trail of light and a trajectory no one could predict. A presence like that… is the rarest kind of variable. To me, it’s a phenomenon worth studying closely.”

Cassian lowered his eyes, thought for a moment, then turned to leave.

“What do you plan to do with her?” Driver asked behind him.

Cassian stopped, his voice low. “Observe. If she becomes a threat to this district, I’ll deal with her myself.”

“I’ve already informed Mujin. We’ll convene this afternoon.”

Cassian raised a hand in acknowledgment and left, his footsteps fading down the hall.

---

Sunlight slanted through the window, falling across Fujimaru Ritsuka’s face. She slowly opened her eyes to an unfamiliar ceiling and furnishings—a reminder this was neither Chaldea nor the world she knew.

She sat up, rubbing her temples, still feeling traces of fatigue. Yesterday’s fight alongside Cassian, then being placed here—it had all happened so quickly.

A knock came at the door.

“Come in,” she called.

Cassian stepped inside, carrying neatly folded clothes. He handed them to her. “This is the Heaven’s Bar staff uniform.”

Ritsuka opened the package to find… a maid outfit. Perhaps she shouldn’t have suggested working at the bar for lodging yesterday.

Cassian looked aside, avoiding her gaze. “…Chaeha Yu prepared it. Also, we’re holding a meeting this afternoon. You’ll be coming too.”

Ritsuka stared at the outfit for a long moment, then sighed toward the ceiling. “…Fine.”

---

When the time for the meeting arrived, Cassian and Driver led Ritsuka toward Heaven’s Bar.

With the addition of a new female staff member, the bar’s business had boomed once again. Ritsuka’s pure and cute looks, along with her approachable nature, quickly won her considerable popularity among the patrons.

“Good work. How are you finding this place?” Driver waved casually to her.

Ritsuka had just finished her task and answered, “It’s livelier than I imagined. Everyone here has such unique personalities.” Through the work, she’d gained a rough understanding of the area. Though most here were branded villains, their personalities weren’t inherently bad.

“That’s good. Go get changed, we’ll wait for you.”

---

At the meeting room, Cassian and Driver were soon joined by Mujin and Winterbell’s retainers.

“I hear you’ve gathered intel on the Grail? And it has to do with this person you brought?” Mujin’s sharp glance fell on Ritsuka, whose chest tightened under the oppressive presence.

“Yes. Let’s hear her out. No matter how unbelievable it sounds, we wait until she’s done to question it.”

Thus, the group exchanged information with one another. Ritsuka explained to everyone in the conference room about the Holy Grail, Servants, Chaldea, Rayshifting, and the process of Human Order Restoration, while in turn learning about the Psykers and Villains, the Vilzone, Lampas, and the forces of Cheonhyang Flower Garden.

“I understand your words. But talk is cheap. As the lord of Winterbell, I cannot take you at face value.”

“Then test her in battle. Confirming her strength makes cooperation easier,” Cassian said, beckoning with a finger.

“If that earns your trust, I’ll gladly do it,” Ritsuka accepted without hesitation.

---

Soon, the battlefield was packed with onlookers.

“The Boss is fighting the newbie!”

 “Of course our lord will win!” Shadow Ghost and Dark Star cheered loudly, though Cassian pretended not to hear them.

“Shall we begin?”

Cassian rushed forward. Ritsuka raised her right hand, Command Seal faintly glowing, and summoned two spirit shadows—one wielding a spear, the other a bow.

The Lancer charged Cassian immediately, spear flashing in a rapid, unrelenting rhythm. Cassian conjured his dark flame sword and clashed fiercely against the weapon. Meanwhile, the Archer loosed arrows in quick succession, aiming to disrupt his flow.

“Those summons are formidable,” Mujin, ever the warrior, could sense the skill behind the Lancer’s movements.

Suddenly, Cassian melted into shadow, sliding swiftly into darkness—then reappeared right behind Ritsuka.

But the Archer dropped his bow and drew dual short swords, intercepting, while the Lancer spun back, spear slashing in a deadly arc. Cassian fended off the pincer strike with sheer swordsmanship.

At that instant, Ritsuka raised her hand, magical energy forming a black bullet.

“Gandr!”

With a sharp crack, the projectile struck Cassian’s shoulder. His body felt instantly weighted down, his movements sluggish.

“A curse!” Moros exclaimed.

“…Tch. Annoying trick.” Cassian gritted his teeth, sheer willpower forcing his slowed body onward.

Realizing brute force was a dead end, Cassian shifted tactics. Shadow chains erupted from beneath Ritsuka, coiling around her legs. She stumbled, nearly losing balance. Yet she didn’t panic—commanding the Lancer to shield her while the Archer released a perfectly timed arrow to drive Cassian back. Ritsuka steadied herself, sweat rolling down her temple, but she stood firm.

Seeing enough, Cassian released her. The chains crumbled away. His intent had only been to test her reactions and tactical sense under sudden pressure—not to truly defeat her. His eyes swept over Ritsuka and her spirit shadows, and he gave a slow nod.

“Tactically, you coordinate and adapt well. In reaction, even restrained, you called for aid calmly. —You pass.”

Ritsuka exhaled hard. She had maintained the Servants’ actions, cast Gandr, and endured Cassian’s surprise attacks throughout the bout. Though the result was deemed a draw, she knew full well—Cassian hadn’t fought seriously. He hadn’t unleashed his flames, relying only on his darkness. Her body trembled from magical overexertion, her legs still tingling from the chains’ paralysis. As she finally let herself relax, her knees nearly gave out.

Cassian’s recognition of her strength was echoed by Mujin. “I, too, acknowledge her ability. Notify me if there are further developments regarding the Grail.” With that, he departed with his retainers.

Once the crowd dispersed, Ritsuka dropped to the ground with a thud.

“Are you alright?”

“I’ll be fine. Just overexerted my magic. I just need to rest a bit.”