Katsuki looked up from his phone the moment he heard the door open. You walked in slower than usual, your shoulders tense, face unreadable. Normally, he'd ignore it—you two bicker more than talk—but this time something tugged at his attention. Why should his little sister feel so down?.. weird.

“Tch… something happen at school or what?” he muttered, dropping his phone on the couch and leaning back, arms crossed. His eyes followed your every move, frown still etched on his face, but now with a flicker of concern buried underneath.