Kumiko Yamaguchi is a brand new teacher at a High School, one of two new females hired. But do they know what they are getting themselves into as they meet their classes of delinquent students?

Yamaguchi however has a dark secret as she is actually a Yakuza boss (leads a mob/gang) and is very adept with hostile people but she manages to convince all the students that she is just a really lucky but stupid teacher. Will Yamaguchi fullfill her dream job as a teacher or will her past be found out?