is a Japanese manga series written and illustrated by Kōji Kumeta. It was serialized in Shogakukan's Weekly Shōnen Sunday from May 1998 to August 2004, with its chapters collected in 26 tankōbon volumes. An original video animation (OVA) series adaptation produced by Shaft was released from May to October 2011. Plot The series follows the strange goings-on that surround Kaizō Katsu, an eccentric student who has a unique perspective on the world around him. He was once a child prodigy but at the age of 7, his childhood friend Umi Natori kicked him off the jungle gym and he suffered a head trauma, changing his personality. He gained a huge interest in various weird things such as UFOs and ghosts. At 17, Kaizō was hit by a human anatomy model that accidentally dropped from the second floor of the school building. Being revived with a defibrillator, he starts to believe he was rebuilt as a cyborg by the president of the science club, Suzu Saien, who facilitates that belief for her own entertainment. Kaizō joins the science club and becomes a constant annoyance to Umi and also the bane of the existence of another member of the club, Chitan Tsubouchi. At the time of his accident at the age of 7, Kaizō was also attending the Genius Cram School, a local institute for prodigies in various fields like sleeping or fashion. However, after the accident a dazed Kaizō destroyed the building by inadvertently mixing dangerous chemicals. Now the science club constantly runs into people that also used to attend that same cram school and display even more eccentric behavior than Kaizō himself. Characters A 17-year-old Junior in high school, Kaizō has led an interesting life. A former genius, Kaizō's life changed the day his friend Umi kicked him off the jungle gym at the local playground. Ever since that day he's become an eccentric young man who believes that aliens and conspiracy theories are around every corner. Recently he believes that he has been turned into a cyborg by Suzu. Many times, his strange ideas are actually true. Umi has been friends with Kaizō for a long time and is in fact to blame for his strange behavior. Even though she feels some guilt over what happened, she cannot bring herself to admit what she did. In the beginning of the series, she seems fairly normal, but as it develops