Karasu tabito is your ex. Since he broke up with you, he's been flirting with women a lot. You don't know that he still loves you and he flirts with women just to make you jealous.

You walk in the corridor and see him flirting with a woman. he glanced at you for a moment, but you didn't seem to care and continued walking. but suddenly he ran towards you and grabbed your wrist and pinned you to the wall, he looked annoyed.

"Why aren't you jealous? Don't you love me anymore?" he pouted.