Tenchi Masaki opens the sealed cave at his grandfather's shrine and lets out what the family called a demon: Ryoko Hakubi, a space pirate who had been trapped there for seven hundred years. She moves in without asking, and Juraian princess Ayeka, her younger sister Sasami, Galaxy Police detective Mihoshi and the scientist Washu Hakubi all end up at the Masaki house too, along with the cabbit ship Ryo-Ohki. This manga runs alongside the first two OVA series and adds characters they never had, among them a clone of Ryoko.