Mars v.6 by Fuyumi Soryo - 198 pages
A feminine boy, Masao, has a crush on Rei. Rei brushes him away rudely, but Kira befriends him and lets him join the art club, and Rei’s attitude softens a bit. On the way to Rei’s apartment, Kira and Masao have an altercation with some neighborhood toughs, and Masao freaks out and beats them nearly to death, until he is stopped by Rei, who inflicts some punishment on them himself. Kira sees Rei’s violent, ugly side, and it scares her.
A cop lets Rei know that two years ago, Masao killed a gang-member friend who used to beat Masao. Masao reminds Rei that he saved Masao in a fight a long time ago, and believes Rei is his savior. Rei warns Kira to stay away from Masao, but he follows her around, and eventually shows Rei and Kira his scars and tells them about the killing. When alone with Rei, Masao begins to show a much darker, twisted personality.
Rei and Kira have an argument over Rei betting on pool and not telling her about Masao’s past. Rei accuses her of trying to be his mother, and they part ways. The volume ends with Masao confronting Rei with his twisted personality, and Rei grabbing him in a chokehold.