School Days is a particularly infamous series. Based off of an eroge, the anime is notorious for its bad ending, as well as how it turns the harem genre completely on its head. This makes for particularly compelling characters to be both loved and hated.
Of the School Days characters, there was one in particular that caught my attention, and not from hatred, like many of the other characters in School Days.
That character is Kotonoha Katsura.