older sister. She is the former leader of a powerful street gang, and her favorite hobbies are drinking, beating up Seiji, and taking his allowance. She was the one who taught him how to fight when they were young. A childhood friend of Midori's who is also a fellow first year at Ogurabashi High School. He was always in love with Midori, but over the course of the series, he manages to develop feelings for Seiji that make the miniature Midori extremely nervous. A year-younger student at Seiji's school and kōhai or underclassman of Seiji. He idolizes Seiji for his fighting skills and is arguably the closest thing to a friend Seiji had before Midori. However, he seemingly can not keep himself out of trouble as he constantly gets caught by rival gangs. A classmate of Seiji's who is a doll otaku. He always carries around a doll of a fictional anime character named Ultra-Marin, and seems to have a creepy obsession with the character. He is also good at making clothes for dolls, a talent which means an expanded wardrobe for the miniature Midori when he finds out Seiji's secret. A 10-year-old neighbor of Seiji's who has a crush on him. She tries a variety of ways to gain his attention, even going as far as asking Rin what kind of woman Seiji likes. However, he never takes her advances seriously as he still treats her like a child. Midori's mother who is worried about her. Haruka is willing to do anything to cure Midori of her illness. She is very sad about Midori's coma and tries several times to bring her back. Other characters She is an American exchange student who transferred into Seiji's high school (more precisely, into Miyahara's class). She loves Japanese pop culture, especially samurai movies, and admires Seiji because she sees him as an ideal Japanese man. A silent, mysterious girl in Seiji's class. She loves strange phenomena, and thus takes an interest in Seiji's transformed right hand. She seemingly appears at the strangest times, which gives Seiji quite a scare. Nao's father who is a doctor. He always attempts to capture Seiji so he can dissect him to show Midori to the medical community and gain fame from his findings. While his attempts are usually foiled by Nao, Seiji and Midori occasionally do this as well. Rin's boyfriend, Sakisaka is a treasure hunter