High school students Takeshi and F1 were working part-time to earn money by stealing mopeds and selling them to delinquents. One day, Ayaka, who has transferred to the school Takeshi attends, joins them, and the three of them decide to steal a moped. When he tries to steal a moped parked in his apartment, he is found by a woman wearing a mask who seems to be the owner. Takeshi and his friends escape on a motorcycle, but they are quickly overtaken by a running woman with unbelievable physical abilities. This masked woman was a slit-mouthed woman who ran 100m in 6 seconds with her mouth split all the way to her cheeks.
The story is set in Abashiri, Hokkaido, and follows a high school student, Nagi, who transferred from Osaka.