While on board a train to Tōkyō to meet up with her boyfriend Shōji after a long time apart, 20 year old Nana Kōmatsu (A.K.A. Hachi) happened to sit beside 20 year old Nana Ōsaki, who was traveling to Tokyo to fulfill her dreams of becoming a musician. The vocalist for her punk band 'Blast', Nana's goal is the debut for 'Blast' in Tōkyō where her ex-boyfriend, Ren, is the guitarist for the popular band 'Trapnest'. Sharing the same name and age, both girls quickly form a bond of friendship. In addition, fate seems to play a part, as they both end up looking for the same apartment at the same time, and soon move in together. Together, the two go through their love lives and peruse their careers in the city of Tōkyō.