Hiroyuki Kanbe

Kyousuke's smart, cute, but bratty younger sister hates him. While they used to get along when they were very young, over the years they grew more and more distant until finally they stopped talking altogether, doing their best to ignore each others' existences. One afternoon Kyousuke finds an anime DVD case he doesn't recognize, which hid a very inappropriate ero-game. (myanimelist.net)