I don't really understand this other definition some people speak off, but in my case... I'll make it short, a tsundere (to me) is a person who is wild in nature but
switches mood like crazy. Take for example, the 3rd picture that KaneDragon posted, Kyou's mood when she threw that dictionary at Sunohara's face was wild, then she became embarrassed when Sunohara commented about something he saw, then switches back to her wild side.
