The scratching stopped.
Tanjiro pressed his ear against the wooden door frame, but silence felt worse than the sound. Through thin walls, he caught fragments—muffled whimpers, breathing that shifted between human and something else.
"Nezuko?" He kept his voice soft. "You all right?"
Rustling fabric. Footsteps across tatami mats, uneven rhythm. "I'm fine, brother." Her voice carried a rasp that raised every instinct he possessed. Like something had scraped her throat raw from inside. "Couldn't sleep."
"Can I come in? You sound—"
"No!" Sharp response, then heavy silence. More controlled: "I mean, I'm getting dressed. I'll be out soon."
Wrong. Everything about this was wrong. His nose picked up scents that shouldn't exist in his sister's room. Fear, confusion, and underneath—something metallic. Something that reminded him of demon presence.
"You don't sound fine. Your voice is different."
"Just dry throat. Mountain air." Forced laugh that cracked halfway through. "Nothing to worry about."
"The mountain air never bothered you before."
Something heavy dragged across the floor. "I'll drink more water. Really, Tanjiro, I'm fine."
But she wasn't. The scent profile told a different story—stress markers he'd learned to recognize during dangerous missions, layered with something new that made his protective instincts scream.
"I'll wait for you at breakfast."
"You don't need to wait. I might stay in my room. Still tired."
Nezuko never avoided meals. Never hid from him. Never made excuses about fatigue.
Something had changed during the night.