If My Wife Becomes an Elementary School Student.

Keisuke Niijima has been living without his wife, Takae, since her passing 10 years ago. His daughter Mai is his only family, but he's always been more of a provider than a hands-on parent. The distance between them has grown over the years as they live in the same house but lead separate lives. A young elementary school girl claiming to be the reincarnation of Takae suddenly appears at their doorstep, forcing Keisuke to reevaluate his relationships.