As a child he was friends with Chihiro until he one day fell down stone steps and developed brain damage while she was moved to the States. As a result, he endured his time with no friends and was bullied constantly. He spent his days watching nothing but porn and eventually his own parents gave up on him even telling his little brother not to be like him.
Chihiro eventually returns to Japan and learns of Ryouichi's life. Blaming herself for the accident, She asks Ryouichi for anything. Taking advantage, he asks for sex. At a hotel, he soon learns he is completely infallible and decided to use his stamina to get revenge on all the females who bullied him by raping them. Chihiro reluctantly assists him out of guilt.
After raping several students and even his lesbian teacher, he gains a following of female admirers, but Chihiro eventually gives up on being with Ryouichi and moves back to the States. On the plane, Ryouichi is waiting for her and they have sex in the airplane bathroom. Chihiro is happy to be with Ryouichi again and he thinks about having sex with as many American girls as possible.
- While he is muscular in the first OVA, he becomes more slim in the second and third OVAs.