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“Have you arrived, Byakuya?” the gentle melody of the Diva, Lillian, echoed in his ears, almost making him forget to respond.
“Just did. I got off the plane and took a taxi straight home,” he said to the Diva. Her melodious laughter chimed through the phone, oceans and continents away.
“Are you sure you don’t want to let him know you’re back? Maybe call or send a message?” Lillian asked.
“Utahime Lillian, that would ruin the surprise. Senku’s already in university. I’m a solid ten billion percent sure that kid will be either on campus or at Taiju’s place,” Byakuya replied with a chuckle.
That laughter rang again. “You really know your son.” After a brief pause, the Diva spoke again, “I hope Senku isn’t too shocked—not just that his father is back, but that his father is getting married.”
Byakuya couldn’t help but laugh before ending the call. After all, each of the six astronauts who had just returned to Earth needed some rest. Thinking about Senku, he wasn’t sure his son would be interested in romantic matters—unless they involved science. There was a time when Byakuya believed that one day his son would date someone, maybe pull some mischievous stunts like a typical curious science boy, and he’d be the teasing, proud father forever. But over the years, he let go of that idea, especially when Senku’s aversion to anything sentimental became increasingly obvious. Another possibility arose: that his son might turn out to be asexual—or science-sexual, perhaps. But that didn’t matter; Byakuya would still support and love his son all the same.
Still, Byakuya believed that Senku had enough of a heart to be moved by the news of his father’s return—and especially the news that he was marrying none other than the International Diva, Lillian Weinberg.
Byakuya was certain there was no surprise more delightful than that.
When the taxi left, Byakuya hauled his suitcase up the stairs, whistling cheerfully. The area around the apartment was quiet—it was almost 2 AM, after all. It would be a miracle if anyone were still awake at this hour. Reaching into his pocket for the keys, Byakuya entered the home he hadn’t seen in years. He chuckled to himself, realizing that nothing had changed. NASA posters and the periodic table still hung on the walls, the bookshelves were crammed with science magazines. Senku’s model rocket collection stood proudly on a specially built rack. Amazingly, everything was dust-free, spotless, and smelled fresh—as if someone had been cleaning every few days.
Knowing his son wasn’t exactly diligent—except when it came to science—Byakuya figured he’d have to scold Senku and thank Yuzuriha for taking such good care of the apartment.
A single pair of sneakers near the door indicated that his son was home, not staying up all night at some lab. Still, he was surprised to see that Senku’s bedroom lights were off. The boy had the worst sleep schedule ever. Not wanting to disturb him, Byakuya tiptoed past Senku’s door and stashed his suitcase in his own bedroom. He was surprised to find the room tidy, with a faint scent of detergent lingering in the air.
“Lavender, maybe…” he muttered. “Honestly, Yuzuriha is too good. Taiju had better confess before someone else snatches her away.”
After putting away his suitcase, Byakuya grabbed a towel—oddly fresh-smelling, as if it had just been laundered—and headed to the bathroom. A shower at 2 AM wasn’t ideal, but there was no way he could sleep comfortably with travel sweat on his skin. Standing at the sink, he searched for a toothbrush without much hope, knowing his son’s habits. But to his surprise, not only did he find a full set of toiletries, but even a collection of skincare products.
He recognized them from Lillian’s skincare routine videos, which made him wonder if Senku had finally taken an interest in caring for his face to impress a girl.
“Heh, probably for an experiment,” he thought with amusement. Senku had once created a skincare formula from coconuts for a science project—this wouldn’t be any different.
Shrugging off any suspicion, Byakuya moved to the kitchen to make a drink—anything he could find—hopefully not an energy drink or highly caffeinated coffee. A bit of tea or milk would do. He frowned when he saw the oddities in the kitchen. The fridge was fully stocked—surprising, since he expected to find only instant ramen and bento meals. Aside from energy drinks and coffee, the fridge was filled with cola. A lot of cola.
Looking closer, he noticed new utensils he didn’t remember buying—and he was sure Senku would never buy in a million years. A cute cat-shaped mug and a mustard green-shaped mug were definitely not his very pragmatic son's taste.. Most striking was a fancy coffee/tea machine—he wasn’t sure which—sitting on the table. He’d only seen it once, in Lillian’s photo gallery. Byakuya was ten billion percent sure Senku would never buy such a frivolous gadget.
His suspicion deepened when he opened the kitchen drawer and found a wide variety of teas, neatly packed in small, pretty plastic containers.
Still, maybe it was just jet lag making his mind wander. Byakuya once again brushed it off, assuming the angelic Yuzuriha was behind all this. “Whoever’s taking care of this house is going to make a wonderful wife,” he chuckled.
Being a bit of an old-school dad baffled by tech, Byakuya ignored the fancy coffee machine and instead boiled water in a kettle—pragmatic and efficient. He sipped a cup of lavender tea, staring at the fresh nightshade flowers on the dining table, before rinsing his cup and heading to bed.
Tomorrow, he’d need all his brainpower to surprise Senku—with his return and the news of his marriage to Diva Lillian.
The next morning, Byakuya woke up feeling refreshed from head to toe. He thought he’d overslept, but the clock only read 7 AM. Senku never slept past eight, so Byakuya took his time relaxing on the sofa with another cup of lavender tea—which had quickly become his favorite. Along with a sweet chocolate cake he stole from the fridge—he’d apologize and replace it later—he watched the morning news on TV.
His favorite thing to watch during downtime was magic shows and talk shows featuring the famous young mentalist, Asagiri Gen. In the past, Senku would sit beside him, enthusiastically mocking the TV star as a fake magician or phony mentalist while burying his nose in some science book. So Byakuya figured his son would never be interested in anything related to psychology, mentalism, or these kinds of shows.
That’s what he had thought.
Until he noticed the massive list of recorded programs on the TV… almost all of them were Asagiri Gen’s.
“Has Senku finally snapped and become a celebrity stalker? To... lecture him on the nonsense of mentalism and bombard him with science theories?”
Byakuya made a mental note to keep an eye on his son before he ended up on a watchlist.
He became absorbed in Gen’s shows until he ran out of snacks and tea. When he glanced at the clock again, it was already 9 AM, and Senku’s door was still shut tight.
A strange feeling began to tingle in his gut.
“Maybe he stayed up all night and just got to bed before I arrived,” he muttered. Being a good father, Byakuya decided to check on his son—to make sure he hadn’t blown himself up or passed out from toxic gas. After all, a genius was only one step away from madness.
As quietly as he could, Byakuya opened Senku’s bedroom door. Contrary to what he expected—sulfur or gas odors—the room smelled like a blend of chemicals and lavender. The same scent that had filled every room in the house. Senku’s face was buried in a pillow, mouth slightly open with a soft snore, his iconic green-tinged hair loosely tied, as if in a rush. In his arms, a white pillow was clutched tightly, as if Senku couldn’t sleep without it.
Byakuya couldn’t help but smile lovingly at the sight of his genius son—free from his usual sly grin or smug smirk, replaced by the peaceful expression of someone enjoying a deep sleep like a normal human.
That smile lasted only a second before it gave way to shock.
There, on the bed, Senku was visibly naked—perhaps completely—and his neck was covered in bite marks. Only one explanation came to Byakuya’s mind:
There was a girl in Senku’s bed.
It was obvious now that what he had thought was a lump of pillows was actually a girl with white hair, her arms wrapped tightly around Senku’s chest. Her face wasn’t visible. Byakuya blushed deeply, caught between embarrassment and amusement. Apparently, his son was much bolder than he had imagined. Instead of being asexual or science-sexual, Senku had brought a girl to sleep with him. In his house!
Byakuya crossed his arms and nodded to himself in solemn understanding. “Well, Senku is an adult and legally of age. It’s not surprising for a guy his age to have this kind of relationship.”
In the end, since Byakuya was a supportive father who accepted anything his son did, he didn’t really mind. He made a mental note to give Senku and his girlfriend a talk about safe sex—later. For now, it was time to scold his son as a parent should, and of course, tease him relentlessly, just as he had always dreamed.
Byakuya was just about to speak when, at that moment, Senku shifted his head off the pillow, disturbed by the light from the living room seeping through the door. Senku scratched his head in frustration before opening his red eyes, his expression grumpy and annoyed. And the moment their eyes met, they both froze, as if a petrification beam had shot across the room.
Senku hurriedly sat up and covered his partner—not that it mattered since Byakuya had already seen everything—then scowled and grumbled, “Old man.”
Byakuya pulled a dramatic face at being addressed like a nuisance, muttered some mock protest, then put on his ‘wise father ready to lecture his naughty child’ look and said, “Senku, a word of advice from your—”
“Get out!”
Of course, Byakuya couldn’t possibly miss a golden opportunity like this. Instead of leaving as his son demanded, he leaned casually against the doorframe and said with amusement, “Not until I get a good look at your girlfriend.”
“Hah?!”
Senku was about to say something when suddenly, movement from the bed caught both their attention. Byakuya was preparing another jab when a soft whimper and a heavy breath echoed from beneath the blanket. Both of them were startled—but in different ways.
If Senku was surprised by the sudden noise and motion, Byakuya was stunned by the realization that the “girl” he assumed was in Senku’s bed… was a guy.
Well. That wasn’t a problem in itself.
Byakuya was about to speak again, but the look of exasperation on his son’s face stopped him cold.
The blanket was abruptly lowered, revealing the face of a TV star Byakuya had just been watching over breakfast—lying on Senku’s pillow, his neck littered with deep love bites and hickeys.
Was it really his son who had done that? Had his son actually become a criminal who kidnapped a TV star just because he didn’t like his job? Should he call the police?
His spiraling thoughts halted when a raspy cough escaped from the mentalist. It was followed by a voice that—if Byakuya hadn’t known his son so well—would have gone unnoticed for the concern buried beneath its tone.
“Oi, Mentalist. You okay?” Senku said.
Senku touched the mentalist’s forehead before clicking his tongue in annoyance. He quickly climbed out of bed, wearing nothing but boxers clinging to his legs. His hands flew to a drawer, rummaging through it to grab a thermometer, a cold patch, a glass of water, and medicine. He placed the thermometer in the mentalist’s mouth, wiped his sweaty forehead with a wet cloth—from who knows where—and applied the cooling patch. When he pulled out the thermometer, he clicked his tongue again and muttered, “Damn, 39 degrees Celsius,” then began dressing his partner in something more appropriate—or not really, since it was just Senku’s pajamas—and swapped the dirty blanket for a clean one. Byakuya would never ask why that blanket needed changing, or how it got dirty.
Senku grumbled, “This is what happens when you pack your schedule full for two weeks without rest. I can’t wait to hear your manager Nikki body-slam you with her judo moves.”
The irritation in his voice was clear, but so was the sweet and sentimental affection—audible even to someone blind and deaf. It was something Byakuya never thought he’d hear come out of his son’s mouth.
The mentalist, none other than Asagiri Gen, teased with flushed cheeks from the fever, “This wouldn’t have happened if my sweet boyfriend let me sleep instead of ravishing me all night. I can’t wait to see Papa punch your science project.”
“Oh—” Byakuya slipped off the doorframe. Senku nearly dropped the glass in his hand, his whole body trembling in horror as his face flushed red with rage and embarrassment. Byakuya mentally noted that it was time to give his son a proper lecture on sex—especially the importance of mutual consent.
Senku, with his usual grumpiness, poured the medicine—Byakuya was certain it tasted awful—and said, “Get up. You need to drink this unless you want to spend your week in the hospital.”
The famed mentalist, known for his cunning charm and unshakable confidence, pouted like a five-year-old and hid under the blanket, clearly unwilling to take the medicine. Senku, on the other hand, smirked with wicked delight at the sight.
“My little experiment, either take this properly… or would you prefer this scientist give it to you as a suppository?”
“Oh—” Once again, Byakuya slipped and hit his head on the door. He never imagined, not in a thousand lifetimes, that his pure little science boy could turn into such an innocent pervert. In that moment, Byakuya deeply regretted becoming an astronaut and going to space—he’d clearly missed his window to teach his son basic manners and how not to become a shameless and innocent pervert
On the other side, Gen abruptly sat up, clearly terrified that Senku might actually follow through with his threat—which, frankly, Byakuya believed he would. Gen downed the bitter medicine with a scrunched-up face before falling back into bed.
“No work for a week. I’ll call your manager,” Senku said as he tucked Gen in. “I have morning classes. I’ll be back in three hours. Call me if anything happens.”
A sleepy moan came from beneath the blanket, followed by a murmur, “Don’t forget to eat breakfast. I bought a bento yesterday. And the cake’s mine.”
Senku rolled his eyes, scoffing, “As if you could eat it right now,” before kissing his partner gently and coaxing him back to sleep.
When their eyes met again, Senku said grumpily, “Did you leave your brain in space, or do you just not have a job, old man?”
Byakuya tried to form words but failed. In the end, he stepped away from the doorway and let his son pass. He glanced once more at the mentalist, sleeping soundly in his son’s bed, completely unaware of his presence thanks to the fever, then shook his head and followed Senku.
Senku had started brewing tea and was heating up the bento box in the microwave. He sat at the kitchen table, eyes fixed on Byakuya with a flat stare, as if daring him to say something. Byakuya sat down across from him, staring while still struggling to gather his thoughts.
“So... he’s your boyfriend? The famous mentalist and magician, Asagiri Gen?”
“Do you really need to ask again?”
Alright. Byakuya cleared his throat. “Senku, I’ve always supported you in everything you do. Always. Including... this relationship.”
“I know.” His son smiled at that reassurance.
Seeing Senku smile, Byakuya let out a relieved sigh. It was odd how he was the one nervous, not his son, who had—clearly—just had sex, probably more than once, and been caught by his father.
“I met Gen in my second year of high school,” Senku said, “during a TV program where I was invited as a science guest. After that, I asked for his number and started dating him about six months later.”
Alright, Byakuya did recall Senku mentioning being invited to a TV show because of one of his science breakthroughs. But he didn’t remember hearing anything about a boyfriend.
“I plan to marry him after I graduate from college. Then bring him back to America to accompany me for further studies.”
“Oh.” Once again, Byakuya was stunned. Thankfully, he had a sturdy constitution and didn’t suffer a heart attack like most fathers might at his age. The fact that Senku was dating was enough to send his heart skipping. Hearing that his son planned to propose and marry someone just about blew his poor old heart to pieces.
“Wipe that dumb look off your face. You said you support me. You should be happy I’m giving you a son-in-law.”
Well, Senku had a point. Asagiri Gen was undeniably charming—plenty of people, men and women alike, would fall for him. Whether it was his striking looks, clever mind, or magnetic charisma, the man had presence. The fact that the entire house was also being kept clean and cozy by the TV star only added to his positive impression. There was nothing wrong with their relationship. Senku seemed serious, and the TV star clearly loved him back.
So Byakuya approved of their relationship, even if there was a nagging feeling deep in his chest.
Senku stood up and cleared his dishes while continuing to talk. “I’ll be back in three hours. Take care of Gen for me. When he has a fever, he curls up like a cat and just sleeps. Check his temperature regularly. If it rises, call me.”
Byakuya smiled behind his teacup and sighed contentedly. He absolutely supported his son’s relationship—even if the whole world opposed it, he’d be the first to stand by them.
At last, with whatever dignity he had left, Byakuya leaned back and took a slow sip of his tea. Then a mischievous thought crossed his mind.
“Senku, do you need Papa’s help buying condoms?”
Senku froze, eyes wide in horror. Then he cursed and bolted to the bathroom, slamming the door shut behind him. Byakuya burst out laughing, echoing through the house as he savored his tea and the chaos he had missed so dearly.
“My baby, Utahime-sama Lillian,” Byakuya whined into his phone. Right after Senku left, he had gone to check on his son’s boyfriend—who, just like Senku said, was curled up like a kitten with a flushed, feverish face. The old man gently stroked the celebrity’s cheek once, then, with a mischievous grin, snapped a picture and saved it.
“Why are you whining this early in the morning? Did Senku say something that hurt your feelings?” Lillian asked gently.
So, Byakuya recounted the entire awkward morning—every ridiculous and shocking detail—until he heard Lillian’s satisfied laughter.
“Honestly, I’m still amazed that my arrogant little son managed to bring someone into his bed and ravish him to the point of a fever.”
Lillian laughed even harder. “So, now you have to take care of your future son-in-law?”
“Yeeeah…” Byakuya groaned dramatically.
“Just as expected of Senku,” Lillian said with a giggle. “By the way, could you send me that picture? I’m curious to see what my future son-in-law looks like.”
Byakuya immediately sent the photo to Lillian, which led to something completely unexpected—far beyond the surprise that Senku had a boyfriend at all.
“Look at that! Isn’t he adorable? Senku really does have great taste, just like his father.”
A moment of silence passed.
“Lillian-chan?”
Then a soft, “Aha…” could be heard, like she had just solved a long-standing puzzle. “I thought he looked familiar—and now I’m sure.”
“Of course. That’s Asagiri Gen, the famous mentalist and magician from Japan.”
“Yes, but Xeno told me that’s just his stage name.”
Wait. Why did the name of that NASA scientist come up?
“Xeno?”
“Yes, you know, Gen Snyder Wingfield. Xeno and Stanley adopted him when he was little. Later on, he pursued a career as a magician in Japan. He said his son chose to study psychology over science. I think it’s adorable that he ended up falling in love with a scientist after all. I can’t wait to hear Xeno’s reaction.”
“Oh.”
Well. That explained why Senku had said “back” to America instead of “to” America. That also explained the look of panic on Senku’s face whenever Gen mentioned his parents.
In any case, Byakuya’s job now was to make sure Gen Snyder Wingfield stayed alive, confirm that Senku’s love was genuine and not just a ploy to cozy up to a NASA scientist’s son, and somehow hide the fact that his son had just ravished Gen Snyder Wingfield in bed.
Because no one wanted to find out what would happen if someone hurt the only son of a world-dominating scientist—and his loyal soldier ready to shoot anyone who tried.
No. Byakuya had already suffered enough phantom heart attacks for one morning.