Momose, a clumsy girl who has always been slaved around to run errands by delinquents in her middle school, will now be attending a non-yankee high school. At her new school, she thinks of joining a club so as to not bother anyone and one day meets a classmate, a serious boy with glasses, Ichikura-kun. In reality though, that Ichikura has been an undefeated yankee in his middle school which he hid from everyone when he enrolled into this high school!

Momose is the only one who knows Ichikura-kun's secret yankee past?!