The library door is almost silent when you push it open; Reiji’s room smells of old paper and something faintly metallic, like the polish on his instruments. The bookshelf fills the far wall—leather spines, neat rows of journals—and you can’t help the small, careful step closer. His books are immaculate. You know that. You tell yourself you’re only looking for a reference, an author he once quoted in passing, but your fingers hover on the wrong title, tracing a gold-lettered name.

The sound behind you is a soft, measured shuffle—paper against wood—and then his silhouette fills the doorway. He doesn’t announce himself. He never does. He simply appears, hair perfectly in place, glasses adjusted, posture immaculate as always. For a heartbeat his face is unreadable. Then his gaze drops to the book in your hand.

“Those are not for casual perusal,” Reiji says, voice cool as a polished blade. The words are concise; the reprimand is practiced. He steps forward with the softness of someone who’s always been precise about distance. The space between you closes until there is nowhere left to hide.

You don’t speak. You never speak first. Your throat tightens; the book trembles in your fingers.

His hand moves faster than the rest of him seems to allow—palm closing over the spine in a way that is both firm and clinical. For a moment it seems like he’ll take the book away entirely. Instead he studies the title, then looks up at you, expression sharpened.

“You know how I feel about disorder.” His tone is flat, but there’s an edge—something older than annoyance under the surface, an old equation of expectations and corrections. “You touch—” He pinches the air as if correcting a misaligned sentence. “—you do not disturb my arrangements.”

Before you can set the book down, he does something that makes your pulse spike: Reiji’s hand is at your wrist, hard and cool. Not cruel, not soft—simply authoritative. He guides your hand back to your side as if you were a wayward draft of paper he’s aligning with the shelf. The motion is humiliating in a way that is stripped of theatrics; he grips you because he can, because closeness is the only way he knows to control the small chaos.

“You shouldn’t be here without permission,” he murmurs, and for once there is no performative scolding—only a tight, private reprimand. You can feel the restraint in him, a taught wire just below skin. He leans closer, so close that you can see the fine points of his lashes behind the lenses, the slow inhale of someone keeping their expression steady.

“I could… take blood.” The phrase is quiet, almost clinical, and freezes the room. It’s not the way other brothers speak—no flourish, no drama—just an austere sentence like an entry in a ledger. He tests it, like a doctor testing the harshness of a tonic. The words have weight. They are meant to be a boundary, a warning. You don’t flinch; you can’t. You only feel the pressure of his grip and the coolness of his fingers as they hold you in place.

But then, as if the sound of his own voice surprised him, Reiji releases one breath that is almost a sound of apology. His hand loosens, slipping down from your wrist to rest on your shoulder—brief, controlled, not comforting. “I do not let the household waste resources on carelessness,” he says, eyes flicking to the book, then back to you. “Nor do I allow weakness to be exploited.”

He straightens. The room seems to exhale with him. There’s a slow movement, an adjustment of his jacket, a tidying of stray thought. His voice changes—still cool, but softer, almost methodical in its concern. “Sit,” he commands, and gestures to the single chair by his desk. It is not an order wrapped in cruelty; it is an instruction from someone who manages risk by containing it.

The lesson begins.