Imouto & Teketeke

Yuko, an older sister, loses her younger sister, Aoi, during the day. That night, Yuko searches for Aoi and eventually finds Aoi ghost. However, Aoi is with Teketeke. Aoi asks Yuko to find the bullies responsible for tormenting her. She suspects they are Yuko's high school friends. Aoi guides her sister to find the five culprits among ten suspects, meaning five are innocent. Good luck with the sea…