Kumiko “Yankumi” Yamaguchi (Yukie Nakama) lives in the world of Yakuzas as the 4th generation heir of Oedo clan. She is self-sacrificing to protect the weak, she’s tough at fighting, and she firmly believes in the importance of friendship, dreams and family. Yankumi growing in a world different from others makes her view life in a way others couldn't see. That's what she tries to teach her students... she wants to reach them out and convey what she herself learned...

Her ex-boss, Goro Sawatari (Katsuhisa Namase) now works at Akado Gakuen High School as a vice principal. Although the head director of the school board Rroko Akagi (Kyoko Eba) specifically orders him to handle the problematic class, 3-D, it was way too much for him. Sawatari then tried to reach Yankumi and went far away to a southern island to find Yankumi, and convince her to work for Akado Gakuen High School. Yankumi accepted the offer , only to find out that she'll teaching bunch of mean students. Not only that, there are two group fighting over "who'll rule Akodou" thing. Will Yankumi’s strong belief in students and teaching work this time?

Sawatari Goro now works at Akado High School as a vice principal. Although the head director of the school board speficically orders him to handle the problematic class 3-D, the students are just too much for him. So Sawatari goes far away to a southern island to search for Yankumi, and convince her to work for Akado. Yankumi accepts the offer, only to find that her class (again) is full of punks, where two rival groups of students are always at each other's throats. Will Yankumi's strong belief in students and teaching work this time?