Base on Japanese Manga series by Sankaku Head. An anime series adaptation by Doga Koba ran in Japan in 2015. Later second season "Himouto! Umaru-chan R on air from October to December 2017. The sibling gag comedy manga centers around Umaru, Taihei's little sister who boasts beautiful looks as well as prowess in both school and sports; however, "Himouto" (beautiful little sister) has a certain secret.