A Ninja and an Assassin Under One Roof (Japanese: 忍者と殺し屋のふたりぐらし, Hepburn: Ninja to Koroshiya no Futarigurashi; lit. 'A Ninja and Assassin Living Together'), also known as NinKoro (にんころ), is a Japanese manga series by HundredBurger. It has been serialized in ASCII Media Works' shōnen manga magazine Comic Dengeki Daioh "g" since February 2021 and has been collected in six tankōbon volumes. An anime television series adaptation produced by Shaft aired from April to June 2025.

A ninja named Satoko Kusagakure is convinced by her leader Kuro to escape her village with other deserters, but without any money or friends in the outside world, Satoko nearly starves until she is saved by another girl named Konoha Koga, who happens to be an assassin. The two girls quickly form a partnership together: Konoha will rise in the rankings to become a top assassin and defend Satoko from other ninjas seeking to hunt down the deserters from the village, and in turn, Satoko will use her ninja magic to help hide the evidence of Konoha's handiwork and clean up Konoha's apartment.