Imouto sae Ireba Ii Temporada 1 Episódio 7
In order to cheer Haruto up after his anime was such a flop, Itsuki gets him as well as Nayuta, Miyako and Chihiro together so they can play a TRPG. Itsuki usually plays girls in games, but for some reason, Chihiro makes out their character to be Itsukis characters little sister, which leads to Nayuta and Miyako also making their characters sisters of the other two. Haruto becomes the GM and does whatever he wants.