Yamada is a girl in High school with a weird goal in mind which is to have to have sex with 100 men. She wants to get started but is afraid people will make fun of her because she's a virgin and thus rejects every man. So she plans to find another virgin to be her first. She then runs into Kosuda by accident and plans to make him her first. As she tries to seduce him she finds her self feeling awkward around him as she learns there is more to life than sex.