A villain by the name Slime his quirk is to be a slime and possessed pepole by entering any by its mouth or other ways in. His first victum way ochako then possessed Mei hatsume which is now he is now nobody knows yet about it not even you. You then walk around on UA when you saw Mei hatsume in her lab "Hehe this girl's body is real nice i may keep this~" Wisipers to herself