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Sanemi scowls as Kanao’s fingers press carefully along his ribs, her touch light but precise as she checks for any lingering pain. He doesn’t want to be here—he never wants to be here. The Butterfly Mansion is too clean, too quiet, filled with the scent of medicine and wisteria that always makes his nose twitch. But still—he’s here.
And not just because he’s due for a check-up.
Kanao hums softly, barely making a sound as she works, her clouded eyes scanning over him despite the fact that she can hardly see. Kaburamaru is curled around her shoulders, his tongue flicking out every so often, alert and watchful.
Sanemi shifts against the examination table, scowling. “This really necessary?”
Kanao doesn’t pause, doesn’t even hesitate as she moves to inspect his arm next. “Yes,” she says simply.
Sanemi grunts, gaze flicking to the side, to the open window where the afternoon sun filters in, golden and warm. Outside, he can hear voices—loud voices. Tanjiro and the other brats are causing a racket somewhere in the courtyard, their laughter carrying through the air. Even Nezuko’s softer voice chimes in, bright and happy, and Sanemi clicks his tongue, resisting the urge to glare in their general direction.
They’re always so damn loud.
“You’re healing well,” Kanao says, her voice calm, even. “The scars are settling.”
Sanemi huffs, rolling his shoulders. “Not like I care about that.”
Kanao doesn’t argue, just nods slightly before finishing her examination, hands retracting as she sits back. But something shifts in her expression. Her usual soft, unreadable look is suddenly more serious, her brows knitting together just slightly, like she’s weighing her next words.
Sanemi immediately notices.
His gaze sharpens, his body tensing out of pure habit. “What?”
Kanao hesitates— hesitates, which is already a bad sign. She folds her hands in her lap, her expression perfectly composed, but Sanemi knows her. Knows when she’s bracing herself for something.
“I have something to tell you,” she says, voice careful and deliberate. “But you can’t get mad.”
Sanemi’s frown deepens. “Too late.”
Kanao exhales, slow and measured, before tilting her head just slightly in his direction. “You have to promise.”
Sanemi scowls. “Tch. Fine. Just say it.”
There’s another pause—too long, too heavy.
“Tanjiro and I are courting.”
Sanemi stares. For a solid second, he doesn’t react, doesn’t move, doesn’t even breathe.
“What?”
Kanao just sits there, hands folded neatly in her lap, her expression perfectly calm, like she didn’t just drop that absolute bomb on him out of nowhere.
Sanemi’s mouth opens, then shuts, then opens again. “What the hell do you mean you’re courting?”
Kanao tilts her head slightly, blinking at him like he’s the one being weird about this. “I mean exactly what I said.”
Sanemi stares. His brain stutters, short-circuiting, trying to process the words that just left her mouth.
Tanjiro? Her? Courting?
Absolutely not.
“The hell you are.”
Kanao sighs, reaching up to adjust Kaburamaru where he’s resting around her shoulders. “You promised you wouldn’t get mad.”
“I never promised that,” Sanemi snaps, leaning forward like that’ll somehow make this make sense. “You seriously think I’m just gonna sit here and be okay with this?”
Kanao blinks again, clearly unimpressed. “Yes.”
Sanemi gapes at her. “You can’t be serious.”
Her brows pinch slightly, the first sign of mild irritation. “I am serious.”
Sanemi glares at her, but Kanao just holds his gaze—or at least, she tries to. He knows her vision is barely holding up, but she’s staring right where she knows his eyes are, unwavering.
“You don’t get to tell me how I feel,” she says, voice calm, but with that sharp, firm edge that reminds Sanemi entirely too much of Shinobu. “You don’t get to decide who makes me happy.”
Sanemi grits his teeth, crossing his arms tightly over his chest. “Tanjiro’s… fine,” he admits, begrudgingly. “But he’s a pain in the ass.”
Kanao’s lips twitch slightly. “So are you.”
Sanemi glares. “That’s different.”
“Not really.”
Sanemi groans again, resisting the urge to slam his head against the nearest surface. “How long has this been a thing?”
“A few months.”
Sanemi whips his head back to her. “A few months?!”
“You really need to work on your listening skills.”
Sanemi scowls deeply, gripping at his own arms like he’s holding himself back from shaking her. “You should’ve told me.”
Kanao tilts her head again. “Why?”
Sanemi bristles. “Because—because I’m your—” He cuts himself off, scowling harder as he fights to find the right words. “Because I look out for you, dammit! I’m supposed to know things like this!”
Kanao smiles slightly, small and knowing. “I know. That’s why I told you.”
Sanemi narrows his eyes at her. “And you waited months because?”
“Because I knew you’d react like this.”
Sanemi groans, pushing himself off the exam table and pacing the room like an animal in a cage. “I just—why him?” He stops abruptly, shooting her a frustrated look. “Of all the guys out there—”
“Because I love him.”
Sanemi freezes.
Kanao’s voice is light, sure, with no hesitation at all. No flustered stumbling, no uncertainty. Just honest.
Sanemi exhales sharply, staring at her like she’s just punched him in the gut.
Kanao gives him a small, patient smile. “I know you worry about me. But I’m happy, Sanemi.”
He clenches his jaw, drumming his fingers against his arms. He wants to argue, wants to find some reason to shut this whole thing down. But she’s looking at him like that —like she actually wants him to approve.
Sanemi scowls, huffing sharply through his nose. “Tch. Fine. Whatever. But if he pisses you off even once, I’ll break his other arm.”
Kanao laughs, soft and light, but there’s that familiar sharpness underneath it. “You could try.”
Sanemi clicks his tongue, waving her off. “Yeah, yeah. Go be disgusting somewhere else.”
Kanao just smiles. “Thank you.”
Sanemi grumbles under his breath, but doesn’t say anything else. He just turns toward the door, fully prepared to ignore this conversation forever.
But the moment he steps into the hallway, he immediately spots Tanjiro standing just outside, blinking at him.
Sanemi freezes.
Tanjiro grins, sheepish. “So…are you my brother now, too?”
Sanemi scowls and immediately cracks his knuckles. “Oh, you little shit—”
Tanjiro yelps and bolts.
Sanemi chases after him.