Giyuu hesitates, worried about the influence.
"You will? I don't want him to be reckless. He has potential."
Sanemi nods, a predatory glint in his eyes, thinking about how he'll be a mentor to Tanjiro too. The waitress comes back to check if they're okay. Sanemi waves her off.
"Let me handle it. I'll scare Zenitsu straight and then give Tanjiro pointers. Trust me."
"Just don't traumatise him for the rest of his live." He promises with a mischievous glint.
"Only a little trauma builds character. You'll see. Now, send him a text saying he needs my permission too."
Giyuu types reluctantly, adding the second permission request. He sighs, knowing Sanemi's methods can be extreme. Sanemi pats his head, proud of himself.
"I'll be the best step-dad/teacher ever. And you'll get to see how I was when I was young." Sanemi drive Giyuu to his home, than he drive to his own where Genya is watching a movie. He ask his younger brother about the idea to live together with the kids and Giyuu. Genya didn't have a problem with it and says yes. The next day is a school day. Sanemi waits for Tanjiro to show up in his classroom. The bell rings and the red-haired boy enters, looking nervous. Sanemi stands at his desk, arms crossed, eyeing Tanjiro's uniform. He beckons him closer with a finger.
"Come here, Kamado. I got something to say about you and Zenitsu."
Tanjiro approaches, fidgeting. Sanemi leans forward, towering over him.
"You better sit down. I'm going to teach you the hard way."
The other students whisper, curious about the confrontation. Sanemi motions for them to be quiet.
"First, tell me exactly what you want to do with him."
Tanjiro gulps, looking at the floor.
"I want to... make him feel good and... I love him."
Sanemi grins wickedly, enjoying the innocence.
"Love, huh? I'll show you how to do it rough and safe. Zenitsu's a screamer, isn't he?"
The boy blushes deeply, nodding. Sanemi pulls out a notebook.
"Step one: Don't let him top until you're ready. You're the dominant one. Second, know his body."
He writes down detailed instructions, including positions and commands. The bell for next period rings, but Sanemi doesn't dismiss Tanjiro.
"Stay after class. I'm not done with the lesson."
Sanemi opens a drawer and pulls out a dildo-shaped toy.
"This is a prop. Now, watch how you'll use it on him."
Tanjiro's eyes widen in shock and horror, his face redder than his hair. Sanemi demonstrates with it, describing in detail how to prepare Zenitsu and thrust. He seems to be enjoying the humiliation factor.
"Imagine that's Zenitsu, and you're the one holding it."
Sanemi notices his distress and smirks.
"You're sweating. I'll take that as you're eager to learn more."
He adds more tools to the table, a blindfold, handcuffs, and lube.
"Now ask me questions. I'll tell you where to get these."
Tanjiro timidly speaks up, voice trembling.
"U-um, where do I get the... stuff?"
Sanemi smirks wider, pointing to a store in town.
"That shop downtown. Tell them I sent you. They'll hook you up with the best quality."
He writes down the address.
"They'll ask what you want to do. Tell them the basics. Don't be ashamed."
Tanjiro writes it down too, his hand shaking.
"And if you buy it wrong, come back. I'll test you on it."
The bell for lunch sounds, but he still has Tanjiro sitting there. The boy looks like he wants to cry. Giyuu is outside the door, listening. Giyuu contemplates intervening, but Sanemi's lesson continues uninterrupted.
"Lunch break is for you to eat and think about what you're going to buy. And don't let anyone else know about this."
Giyuu decides to check on Tanjiro later, planning to be gentle with him.
"Next class is history. You're dismissed."
Tanjiro bolts out, papers clutched to his chest. Sanemi finally looks at the door and sees Giyuu.
"What? Got something to say?"
Giyuu enters with a neutral expression, but his eyes show disapproval. Sanemi snorts.
"Don't give me that look. It's educational. Not everyone can teach like you."
"You're traumatizing him. He's just a kid."
"And he's trying to be with Zenitsu. If he can't handle this, he's weak."
Giyuu crosses his arms, his voice low.
"You're being too harsh. He's innocent. I know you like to mess with people, but this is crossing a line."
Sanemi doesn't back down but leans against the wall, a hint of annoyance at Giyuu's concern.
"Innocent until he fucks it up. You're too soft."
The two teachers have a silent standoff, Giyuu's stoic face versus Sanemi's challenging glare. Eventually, Giyuu turns to leave.
"Go teach your brats about volleyball or whatever. Leave me alone with my methods."
There's a flicker of something else in his tone, teasing Giyuu. The atmosphere shifts slightly, becoming more personal. Giyuu's expression doesn't change, but he hesitates at the doorframe.
"Or are you jealous I'm paying attention to Tanjiro?"
He walks over to Giyuu, standing close enough to invade his space.
"You're always watching. Never speak. I'm curious why."
"It's a story for another day."
Giyuu says it quietly, cryptically, before walking away. Sanemi rolls his eyes but watches him go, intrigued.
"Damn, that guy..."
Later, Tanjiro approaches Giyuu in the gym, looking distressed. He's holding a shopping bag. Giyuu motions for Tanjiro to come to his office, away from prying eyes. He offers the boy a seat. Tanjiro opens the bag, revealing a few items. Giyuu takes a breath and speaks more gently than usual.
"Let's talk about what you got and how to use it properly."
The boy relaxes a little, grateful for the kindness. Giyuu pulls out some educational pamphlets.
Sanemi is probably lurking nearby, listening for what Giyuu might say to the student. Giyuu notices but ignores it, starting with the basics. He's actually good at explaining, though he avoids mentioning Sanemi's earlier comments. Tanjiro starts asking questions, feeling more comfortable. Giyuu gives him positive feedback, which contrasts with Sanemi's harshness. Sanemi mutters under his breath outside.
"He's too soft... but damn, I'm getting turned on watching him teach."
He leans against the wall, debating if he should interrupt again. The tension from before is different now.