Series by 井上和郎

Naoki Rikka is an unathletic, academically challenged high school boy who lives a rather dull life until he meets Iroha, a magical girl who claims to be his daughter from 20 years in the future. Iroha arrives with the mission to prevent Naoki from becoming an evil overlord, guiding him with her magic while navigating life at his school.

Seiji Sawamura is a feared high school fighter who protects weaker students but cannot find a girlfriend. Midori Kasugano has quietly loved him from another school for years. After Seiji desperately wishes for anyone to be his girlfriend, he discovers that his right hand has become a miniature Midori. Her real body is elsewhere, leaving the two forced into constant closeness. Their early days revolve around hiding the strange transformation and learning how to live together.