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It happened on a quiet Tuesday afternoon in the High School training courtyard.
The late-afternoon sun cast long, amber shadows across the grounds. It was supposed to be a standard, relaxed tactical review. Yuta Okkotsu had just returned from an extended overseas assignment in Africa, and the atmosphere on the field was light. Yuuji and Nobara were off near the vending machines arguing over drinks, while Gojo stood in the center of the ring, gesturing animatedly as he broke down a complex technique for Yuta.
Megumi sat on the wooden porch steps nearby, half-listening. His spiky dark hair was slightly messy, sharpening his shadow blades.
Yuta, still visibly exhausted from his flight, was wiping sweat from his forehead with the back of his sleeve. He was nodding along attentively as Gojo explained a spatial manipulation nuance.
"So if you compress the cursed energy output at the point of release," Yuta murmured, his brow furrowed as he tried to visualize the flow, "it stabilizes the trajectory, right... Dad?"
The word slipped out before Yuta's tired brain could even process it.
It wasn't intentional. It was the result of severe jet lag, months of running on three hours of sleep, and the subconscious, deeply rooted warmth Yuta felt toward the man who had saved his life and guided him through his darkest hours. Gojo had been his mentor, his protector, the closest thing to a father figure he had ever known.
The instant the word left Yuta's mouth, a dead, suffocating silence fell over the training field.
The wind rustling through the pine trees seemed to halt. The birds stopped singing. Even the distant argument between Yuuji and Nobara faded into nothing.
Gojo froze mid-gesture, his hand hovering in the air. Behind his dark blindfold, his Six Eyes widened slightly in surprise. He slowly turned his head toward Yuta, a tiny, amused smirk tugging at the corner of his lips as he opened his mouth to make a teasing remark.
He never got the chance.
Don't.
Gojo's breath hitched in his throat. He didn't even get to speak before an icy, suffocating pressure slammed into the space between them.
Gojo slowly turned his gaze down to his left side.
The teenager had stood up from the wooden porch steps, his body completely rigid. The soft, quiet warmth Megumi usually carried had vanished instantly, burnt away by a sudden, volatile flare of absolute, unadulterated territorial fury.
First, Megumi looked at Gojo.
His sea-green eyes were narrow, dark, and devoid of a single drop of affection. It was a sharp, piercing glare of absolute betrayal, a cold, silent interrogation that demanded to know why Gojo hadn't immediately corrected the mistake, why Gojo had even looked pleased for a fraction of a second. The message was unmistakable: Explain yourself, old man.
Gojo, the strongest sorcerer alive, subtly raised his hands in a defensive gesture, taking half a step back. The man who could warp space itself looked genuinely alarmed, his mouth shutting tight as he silently signaled his complete neutrality.
Satisfied that Gojo was properly intimidated, Megumi turned his head slowly toward Yuta.
And returned that initial glare one hundredfold.
If Megumi's look at Gojo was cold, his glare at Yuta was an absolute, arctic abyss.
The air surrounding Megumi grew heavy, the temperature dropping so rapidly that Yuta's breath caught in his lungs. The shadows beneath Megumi's boots flickered violently, writhing like liquid ink across the dirt field, curling upward in dark, jagged tendrils that threatened to swallow the light.
Megumi didn't summon his shikigami, but the sheer, raw malice radiating from his frame made the air hum with dangerous intent. His eyes, usually a clear, calm green, had darkened into a deep, stormy pitch. He took one slow, deliberate step forward, his hands tucked deep into his pockets, his posture tight, deadly, and entirely possessive.
Dad? Megumi's posture screamed without uttering a single sound. You called HIM dad? He is my dad, the glare screamed without making a single sound. Find your own.
Yuta felt the hair on the back of his neck stand up on end.
The Special Grade sorcerer, a man who had faced down terrifying curses across the globe, found himself taking an involuntary step backward under the sheer, unhinged weight of a fifteen-year-old's possessive wrath. Rika's spirit stirred faintly within Yuta's shadow, sensing a threat, but Yuta quickly suppressed her, realizing with a wave of severe panic what he had just accidentally done.
"Fushiguro-kun..." Yuta stammered, his face going completely pale, his hands flying up in a frantic, apologetic motion. "I... I'm so sorry! It was a slip of the tongue! I'm completely exhausted from the flight, I wasn't thinking, I swear I didn't mean..."
Megumi didn't say a word. He didn't blink.
He just kept walking forward, his icy, lethal glare pinned straight onto Yuta's soul. Every step Megumi took seemed to make the air heavier, the shadows on the ground stretching out toward Yuta's boots like reaching hands.
It wasn't a tactical threat. It was pure, unadulterated territorial claim. Yuta had crossed a line that Megumi guarded with his entire life. Gojo Satoru belonged to him. Gojo was his father figure, his anchor, the man who had raised him, bought his food, carried him when he was sleepy, and tolerated his sharp edges since he was six years old.
Nobody else got to use that title. Nobody.
Yuuji and Nobara, returning from the vending machines with juice boxes in hand, stopped dead in their tracks twenty yards away.
"Uh..." Yuuji whispered, his eyes wide as he watched the dark, swirling mass of shadow energy radiating off Megumi. "Did Okkotsu-senpai accidentally step on Divine Dog's tail...?"
"No," Nobara whispered back, pulling Yuuji behind a pillar. "He committed a capital offense. He tried to claim the guardian. We need to stay very, very quiet if we want to survive the afternoon."
Field training was officially over.
Yuta swallowed hard, slowly backing away toward the dormitories with his hands raised high in absolute surrender.
"I'm going to... go unpack my bags. In my room. On the other side of campus. Immediately."
Megumi stood his ground in the center of the yard, watching Yuta retreat with an unyielding, razor-sharp gaze until the senior student completely vanished inside the building and the door clicked shut.
Only when the threat was entirely eliminated did the heavy, suffocating shadow energy slowly recede back into the earth.
Megumi stood in the quiet courtyard for three long seconds, taking a deep, slow breath to settle his chest. He turned on his heel, his dark hair swaying with the movement, and marched right back over to Gojo.
Gojo hadn't moved an inch, watching his ward with a mix of awe and deep, foolish affection.
Megumi didn't say a word about what happened. He simply reached out, grabbed Gojo's large hand, forcefully intertwined their fingers in a tight, unyielding grip, securing himself firmly against his father's side.
Gojo let out a soft, warm laugh, squeezing Megumi's hand back tightly and resting his chin atop the boy's spiky black hair.
"Message received, kiddo," Gojo murmured gently, kissing the top of Megumi's head. "Message loud and clear."
Megumi buried his face slightly into Gojo's uniform jacket, letting out a quiet, huffy sigh, content once more now that his world was right back where it belonged.
The next morning, Yuta did not come to training.
He sent a text to Gojo that simply read: "I'm sick. Very sick. Possibly dying. Please tell Fushiguro-kun I'm sorry and that I will never, ever make that mistake again. I'll be in my room. With the door locked. For the next three to five business days."
Gojo showed the text to Megumi, who read it with a blank expression.
"That's probably for the best," Megumi said flatly.
"You scared him," Gojo said, his voice teasing.
"He should be scared."
"Megumi."
"He called you Dad."
"He was tired."
"That's not an excuse."
"It was an accident."
"Still."
Gojo sighed, but there was a fond smile on his face.
"You know you can't keep me all to yourself forever, right?"
Megumi looked up at him, his green eyes sharp.
"Watch me."
Gojo laughed, pulling Megumi into a one-armed hug.
"You're terrifying, you know that?"
"I know."
"I'm proud of you."
"Shut up."
"Love you too, Megs."
Megumi didn't respond, but he didn't pull away either. He just leaned into Gojo's side, his expression softening, his territorial fury fading into something quieter, something warmer.
Later that day, Yuuji found Yuta hiding in the library, surrounded by stacks of books he wasn't actually reading.
"You okay, senpai?" Yuuji asked, sitting down across from him.
Yuta looked up, his eyes haunted.
"I saw my life flash before my eyes," he said quietly. "I saw Rika. I saw my childhood. I saw the light at the end of the tunnel."
"That bad?"
"Worse."
Yuuji nodded sympathetically.
"For what it's worth, I think you handled it well."
"I ran away."
"That was the smart move."
"I'm a Special Grade sorcerer. I ran away from a fifteen-year-old."
"A very scary fifteen-year-old."
Yuta buried his face in his hands.
"I called Gojo-sensei 'Dad.' In front of Megumi. I'm lucky to be alive."
"You are," Yuuji agreed. "But hey, look on the bright side."
"What bright side?"
"You'll never make that mistake again."
Yuta let out a hollow laugh.
"No. No, I won't."
And somewhere across campus, Megumi sat on the porch steps, his hand hooked into Gojo's jacket pocket, his shoulder pressed against Gojo's side.
Gojo was rambling about something, some story about a souvenir shop and a display case, and Megumi was half-listening, his eyes half-closed, his body relaxed.
It was a quiet afternoon. A peaceful afternoon.
And Megumi intended to keep it that way.
Anyone who tried to claim what was his would learn very quickly that there were fates worse than death.
Just ask Yuta Okkotsu. Simple as that.