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Sakamoto had noticed that something was very weird with Shin recently. He had been acting like he was on edge every second, as if letting his guard down would cause something to happen. He was acting really, really strange.
Sakamoto had noticed and endured the abnormal behavior for a week now.
It all started after a mission:
“Shin, dinner’s ready—what are you doing?” Sakamoto entered the room to see Shin flinch and hide under the blanket.
“Yeah, I'm coming!” Shin said nervously, avoiding his gaze.
Sakamoto nodded suspiciously but ignored it.
But then it happened again, and again, and again.
Whenever he showed up unannounced, Shin would run away, create a lot of distance between them, or make him leave the room altogether.
Sakamoto woke up immediately upon hearing some cluttering from his kitchen.
His feet moved stealthily toward the kitchen, his breath stable and calm.
He crouched down, ready to attack at any second. He analyzed all the surrounding tools and identified how to use them against the intruder.
Who was breaking into Shin's apartment at night?
Then the sound of something falling echoed, and he jumped to see—Shin?
Shin flinched and fell back on the ground. “Mr.—Sakamoto? What are you doing here!?” he asked as if he wasn’t just sneaking around.
Sakamoto looked at him and let out a sigh of relief. “I should be asking you that. Why are you up at—2:30 a.m.??”
Shin looked around. “Uh… I'm—midnight snack!!” he yelled out of nowhere.
“You’re… a midnight snack? What?”
“No! I’m just hungry right now!”
Sakamoto looked at the weird list of ingredients spread across the floor: boiled eggs, leftover chicken, banana, blueberries, milk, cereal, cup of noodles, and rice.
He looked at Shin next, not knowing what to ask.
“Um—I’m stress eating! You know, the training is crazy—so I’m just really hungry—yeah…” Shin stammered, trying to explain.
“For how many people exactly?”
“Uh… one?”
Sakamoto’s suspicious gaze didn’t waver once. But he waved his hand. “Fine, but go back to sleep soon, and if you’re sick, you’ll manage on your own.”
Shin nodded and dashed toward his room with all… the food.
Sakamoto yawned and went back to bed.
That was until he heard the cluttering again. This time, he didn’t even make it to the kitchen when he saw Shin running back to his room with more weird food combinations.
Then it happened the night after, and then again after that.
It didn’t happen again until—
“Hey, I need some money.” Shin demanded shamelessly, as if Sakamoto was just supposed to give it to him.
“Why?”
“Personal stuff.”
“How much?”
“¥3450.”
“…”
“Please…”
Now that was surprising. The child who only threw curses and jabs at Sakamoto was actually saying “please” for something?
“Hey! What do you mean surprising!? I’m nice enough to you! Matter of fact, you don’t even deserve that.”
“Oh.” Right, he can do that.
“Yeah, I can. So… are you gonna give it or what?”
Sakamoto sighed for the millionth time that month and took out his trusty wallet to give Shin ¥3500.
“Oh—thanks… I’ll return the extra.”
“No need, keep it.”
Shin looked at him and nodded gratefully.
After that, there were no midnight snacks.
Other than the fact that Sakamoto wasn’t even allowed to enter his room now.
Every time he was about to enter, God knows how, Shin always appeared and stopped him.
Huh. Interesting.
Something was definitely weird with Shin. Though Sakamoto would ignore it if Shin’s life wasn’t in danger or if someone’s life wasn’t in danger because of Shin—he had just been acting so strange. Even Sakamoto was starting to question whether everything was okay or not. Had he missed any chapter on puberty that made this kid act like this? Because what’s going on here?
Sakamoto stared at Shin, looking for any evidence that something was wrong, but Shin just avoided him completely, which confirmed that he was, in fact, hiding something.
Sakamoto sighed. “What’s going on?”
Shin looked at him nervously. Sakamoto saw the sweat starting to form near his ears, the way his eyes refused to look at him, the slight stretch at his lips, the twitch at his forehead, and the tense shoulders.
“You’re hiding something,” he finally confronted after a week of ignoring it.
Shin froze. “Uh—no? And why do you care anyway!?”
Sakamoto sighed again. He wasn’t great with kids, especially the ones going through a volcanic eruption of hormones and overflowing emotions, ready to dash at anything and everything.
“If I find out you’re hiding something important, you’re dead.”
Shin squeaked. “Why are you so obsessed with killing me!?” He backed away, protecting his neck.
I can still stab your heart or use your own hand to crack your neck.
Shin looked at him in horror and backed away even more—oh, he heard that.
“Fine, hide your secrets, but don’t let them interfere with me or your training.”
“Yeah, of course, haha…” Shin laughed nervously and shut himself in his room.
Sakamoto stared at the door, thinking over and over if he had missed any instances where something could have bothered him. After the mission, everything was alright. Shin was back home safe, and Sakamoto had gone to headquarters to give them the report. Had something happened then? Did someone bother Shin?
Is this what teenagers do? Is he reading too deep into this? Is this puberty-related?
Oh—is he… is he… frustrated like—that..?
Sakamoto gasped in shock as the realization hit him—of course!
His eyes widened as the situation finally sunk in. He’s a teenager! He must be frustrated like that. But there’s no reason to hide it. Is he embarrassed?
Wait, is he embarrassed because he doesn’t know about this?
Wait.
Sakamoto’s glasses cracked.
Does… does he need to have the talk with Shin?
Sakamoto’s world exploded. He took out his phone and instantly Googled a bunch of things.
‘How to have “the talk” with a teenager?’
‘How to have “the talk” with a teenager without making him embarrassed?’
‘How to explain “it” to teenagers?’
‘How to make it less embarrassing for both of us edition?’
Sakamoto lost his mind for the first time ever that day. Is this how Shin feels when he’s overstimulated by thoughts?
Because it’s damn terrible.
He didn’t have a clue how to talk about this with Shin. He was a teenager just a couple of years ago, but he didn’t have to manage anything...
The teachers at JCC had already given all the lessons, and Sakamoto was never… frustrated because of all the fights and distractions.
So he never had to experience this. How does he even tell Shin…?
Meanwhile, Shin was losing his mind. He was about to combust. Sakamoto was so onto him!
And here he thought he was doing an amazing job, but the dude was totally suspicious now!
Shin banged his head against the pillow.
He knew he was being watched—observed—but now he was confronted.
He was basically caught if he didn’t do something about this. He was so done for.
He had thought he was doing amazing until now.
What had he been thinking, trying to hide something so serious from the best assassin!?!?
Was he stupid!?
Sakamoto was watching him like a hawk.
His moves, his breath, his excuses.
And the worst part was—Shin didn’t even know what Sakamoto had figured out!
Shin groaned into his pillow. He was so screwed.
Sakamoto definitely knew something was up. That stare wasn’t just suspicion anymore—it was certainty.
Had he pieced it all together? Was he onto the truth?
Or did he think it was something else entirely?
His thoughts were so stupid and hidden that he was confused about what exactly had been revealed!
Shin groaned loudly and banged his head against the bed.
He looked at the small corner of his room, hidden so the content behind it wasn't visible.
He had to fix this. Quick. Yeah, he could do this!
Sakamoto noticed that Shin was acting even weirder now...
Every time he entered the same room as Shin, he started sweating bullets.
“Shin, what are you up to?”
“NOTHING. BREATHING, NORMAL. NORMAL HUMAN BREATHING.”
Sakamoto blinked. “...Right. So here’s the mission we are going on.”
Sakamoto was sure Shin was sick.
Today, he returned home quicker than normal, and the moment he entered, he saw Shin nervously standing there, stretching out his hoodie to hide his face.
“You okay?”
Sakamoto asked, concerned.
“No—totally feeling not well!” Then Shin ran to his room, coughing? Which sounded... fake.
Shin panicked when Sakamoto was suspicious, but it was even worse when he was not acting suspicious.
Shin sat down carefully, looking at Sakamoto, who was sipping his tea, calmly reading his newspaper.
Oh no. He knows.
“Morning.”
HE KNOWS.
“Shin?”
HE TOTALLY KNOWS.
“You okay?”
“Yeah— I DIDN’T DO ANYTHING WRONG, I’M INNOCENT, AND YOU CAN’T PROVE SHIT.”
“...I just wanted to know if you wanted your breakfast now.”
“Oh... haha— I’m going back to my room.”
Okay, Sakamoto was tired of this.
He stood in front of Shin’s room, ready to turn the doorknob and face whatever was present behind that door, but then Shin jumped in front of him.
“Shin.”
“You can’t go in!” Shin shook his head in disagreement.
“Why?” Sakamoto looked at him with more suspense.
“It’s messy!”
“It’s always messy.”
“It’s—emotionally messy!”
“You just made that up.”
“Just understand already!”
“Is this... the changes?”
“Yeah!” Shin had no clue what Sakamoto meant.
“Okay...” Sakamoto left awkwardly.
Sakamoto finally dragged Shin to the living room and made him sit down.
“Shin.”
Shin avoided his gaze. “W-what?”
“So, at your age... sometimes things get messy.”
Shin looked at him, confused, then a flash of realization hit him. Was Sakamoto telling him that he knew?
Shin almost cried tears of joy.
“Yes! It gets all wet and sticky too!”
“...”
“One time, it got all over my hands, and I was so grossed out!”
Sakamoto’s glass shattered.
“Woah—why are you imagining my death?!”
“Just... stop talking.”
Sakamoto sighed, absolutely mortified.
“Well, since you’re already aware, here’s a magazine to help with any other things.”
He handed Shin a magazine, ‘A TEEN BOY’S GUIDE TO BODILY CHANGES!’ written in bold letters.
This time, it was Shin’s turn to freak out.
“WHY DO YOU HAVE THIS?!” all the colour from shin's face drained out.
“I thought it might—” sakamoto tried to explain.
“I CAN’T BELIEVE SOMEONE LIKE YOU WOULD OWN PORN?!”
“It's not porn—”
“I’M TRAUMATIZED. I CAN’T EVER LOOK AT YOU THE SAME AGAIN—”
And Shin ran to his room again and slammed the door shut.
Sakamoto groaned and murmured, “It’s for educational purposes.”
Sakamoto stood outside Shin’s locked door, arms crossed, mentally preparing himself. He knocked gently.
“Shin... look, I get it. You probably feel embarrassed right now, but you don’t have to hide from me.”
Inside, Shin held it in his hands, panic setting in. “I... I don’t know what you mean,” he stammered.
Sakamoto sighed, pressing his forehead against the door.
“I know it’s confusing at first, but trust me, it’s perfectly normal.”
Shin whispered to them, eyes darting around his room. Shh, he knows! How does he know?!
“Look, I was your age once too,” Sakamoto continued, his tone trying to be gentle. “I understand. It’s weird, it’s messy, and sometimes, it happens when you don’t expect it.”
Shin frowned, glancing down at them. “Messy? What? No, I cleaned up already.”
Sakamoto choked back a laugh. Way too honest, he thought. “O-okay. That’s good. Hygiene is important.”
“Yeah, I mean, it got everywhere. I had to wipe it all up before anyone saw,” Shin admitted, glancing nervously at the pile of tissues on his desk.
Sakamoto winced, rubbing his temples. “...Right. That’s... uh... responsible of you.”
A long silence stretched between them.
“Listen, Shin,” Sakamoto finally said, trying to be reassuring. “It’s a part of growing up. Everyone does it. You don’t have to feel guilty.”
Shin tightened his grip on it, “I—I DO feel guilty! But I couldn’t help it!”
“Exactly. It’s a natural urge.”
“Urge?” Shin repeated, baffled. “I just saw it shivering there, and I HAD to pick it up!”
Sakamoto’s entire body stiffened. “...Wait. What?”
“It was so small and weak! What was I supposed to do, ignore it?!” Shin’s voice cracked.
Sakamoto stepped back, even more confused “Excuse me??”
“And it just kept rubbing against me, and I didn’t know what to do!”
“…what the hell, shin??”
“I—I wrapped it up in a towel! But it was still shaking, so I held it under my shirt for warmth!”
“Huh?!”
“And then it made this weird noise, and it kinda—like—twitched in my hands?”
Sakamoto paled. “...You need to stop talking.”
“But it was just so cute, I had to take it!!” Shin yelled.
A heavy silence followed.
Sakamoto stared at the door as if it had personally insulted his entire family. “I’m sorry. What are you talking about?”
"What are you talking about!?" Shin shouted from inside.
Sakamoto sighed, "clearly not the same thing, so just tell what's going on before I break in."
The door opened, and Shin held up a tiny, what looked like a week-old kitten.
“A.. kitten..?”
Sakamoto stared at the cat. Then at Shin. Then back at the cat.
“…I have never been more relieved and more pissed off in my entire life.”
The kitten meowed softly.
“Move over,” Sakamoto muttered, stepping inside. “I need to sit down.”
“So… I’m not in trouble?” Shin asked hesitantly.
Sakamoto sat on his bed. “You’re dead for making this the most stressful week of my life.”
Shin looked at him, horrified. “Me?! Do you know how much you stressed me out with all your porn magazines?!”
Sakamoto imagined killing Shin just to make him shut his mouth. “They were not porn magazines. They were for educational purposes. I thought... you might need those since you’re going through that phase.”
“Oh—okay.”
Sakamoto looked at the cat. It was white with black spots. “Where did you find this?”
“Somebody left it down the road, and I just couldn't let it stay there due to the weather...” Shin explained, petting the cat and softly scratching its ear.
Sakamoto looked at him and sighed. “In this job, you can’t have pets—” Shin’s mood instantly soured, but Sakamoto continued, “—but till we find it a suitable owner and a good home, we can keep it.”
Shin beamed at Sakamoto and hugged the kitten.
“Well, what’s its name?” Sakamoto asked curiously.
“Rocket Launch Explosion Boy!”
Sakamoto broke shin's neck with the blanket, in this thoughts.
“Why!?” shin yelled.
Sakamoto regretted everything.
Shin was acting like he’d won the lottery, cuddling the tiny furball like it was the best thing that had ever happened to him. And honestly? It probably was. But that wasn’t the problem. The problem was that Shin had zero idea how to take care of a cat.
“Shin, stop shoving its face into your hoodie.”
“But look! It’s cozy!”
“It looks like it’s suffocating.”
Shin gasped dramatically. “I would never! Do you think I’d just let my child suffer?”
“Your child?”
“Yes, Rocket Launch Explosion Boy is my son, and you will respect him.”
Sakamoto rubbed his temples. It was too early for this. He should’ve let Shin dig his own grave instead of stepping in. “First of all, we’re changing that name. Second—”
“Over my dead body.”
“That can be done.” and came 10 ways of sakamoto killing shin.
Shin gasped again, covering the kitten from Sakamoto like he was some kind of evil villain. “You’re heartless.”
But the kitten pured more, just proving sakamoto's point wrong.
“I’m realistic.” Sakamoto took a sip of his tea, ignoring the kitten. “We need supplies. Food. A litter box. Actual cat toys so it doesn’t rip apart your clothes.”
Shin immediately brightened. “Oh! We can take him shopping! I’ll carry him in my hoodie like one of those moms with baby slings!”
“No, we cannot.”
“But why?”
“Because that’s insane.”
Shin looked absolutely betrayed. “You just don’t understand love.”
Sakamoto sighed. “Fine. Do whatever you want. Just don’t come crying to me when someone mistakes you for a insane person carrying a tiny, feral creature in your hoodie.”
“I accept your challenge.”
That was not a challenge.
Shin, however, took it as one.
The next morning, Sakamoto regretted everything again.
“why is it in your hoodie.”
Shin grinned as Rocket Launch Explosion Boy poked its tiny head out. “Because we are one.”
“You are not one.”
Shin adjusted his hoodie, making sure the kitten was snuggled up real good, “I think you’re just jealous of our bond.”
Sakamoto took a deep breath, and decided it wasn’t worth the energy to argue. “Let’s just go. I can't be bothered."
Shopping with Shin was already a nightmare. Shopping with Shin and a kitten hidden in his hoodie? Hell.
Every two minutes, Shin whispered, “Are we suspicious?”
“Yes.”
Rocket decided that was the perfect moment to let out a loud, tiny meow.
A woman in the aisle turned to them.
Shin immediately coughed very loudly. “Sorry, I just—uh—HUMAN NOISES.”
Sakamoto wanted to throw himself into traffic.
They barely made it out of the store without being arrested for public kitten smuggling.
Back home, Shin dumped everything onto the floor, grinning. “See? No problems.”
Rocket immediately ran into the food bag, knocking it over.
Sakamoto stared. “I’m moving out.”
Shin beamed. “Welcome to the family, Rocket.”
Sakamoto regretted everything. He was tired, but the kitten was far better explanation to shin's behaviour.
“Shin, did you read the magazine?”
Shin turned pale, “Yes— ofcourse!” Not.
Sakamoto looked at shin with ‘I know you're lying look'
“Shin, it's important to know that biological changes in your body.” Then he took out a a paper and a pen; and started to draw the diagram of male body. Shin visibly gagged.
He looked at sakamoto horrified as he tried to escape but sakamoto grabbed his shirt and pulled him back.
Shin yelled, struggling to get out but sakamoto trapped him.
“No you don't. So puberty—”
Shin had never screamed so loud in his life before.
And that’s how Shin got himself a cat. And lessons on human biology.