Kakeru Satsuki (younger brother)
Kukuri Satsuki (皐月 菊理 Satsuki Kukuri) is Kakeru Satsuki's older sister. She committed suicide in the bath by slitting her wrist 5 years prior to the events of Sin, Damnation and the Atonement Girl arc, which marked Kakeru. Her reasons for dying is unknown, but in the anime she did it to prevent the world from being destroyed, after having learned the truth from Shiori. Her personality seemed being the same as Kukuri Tachibana and she loved her brother Kakeru, as well as Yuka, very much.