Nana Komatsu is moving to Tokyo to start a new life with her boyfriend - and as chance would have it, she is about to meet a woman the same age named Nana Osaki, with the two Nanas destined to share an apartment.

Nana K. has quite the dating history with men, but when she falls for one of her girlfriend's buddies, is the relationship for real, or just another case of fleeting 'love at first sight?'

Nana K. and Shoji have made a 'declaration of friendship,' but their growing relationship is strained when Shoji decides to move to Tokyo.

Nana O. is a musically talented loner who is about to have her world turned upside down as her guitarist boyfriend Ren ponders a change of scenery.

Ren is committed to hitting the big time as a musician in Tokyo, but is Nana O. content to come along for the ride, or stake her own claim to fame?

A chance encounter on a train brings Nana K. and Nana O. together, and another chance meeting leads to them sharing the same apartment.