Chika, Ryo and Nao are friends who have sex with Nao being the bottom, until he asks Chika if he wouldn't want to try to be the bottom once and it changes all the dynamic of their relationship. In the middle there was a story about a uncle and a nephew that witnessed said uncle having sex when he was young and fell in love, 4 years later he went to his apartment to have sex with other people with him in the room.
The story was good, but after they made some kind of promise it good pretty confusing until I understood it was about only kissing, but it still didn't clear everything. The uncle and nephew story really ruined everything, shouldn't exist.
Chika-chan to!