Lost Universe - Season 1 Episode 9 Lost Lavatory

The trio receives an SOS call from a ghost ship in the asteroid belt, known as ""a graveyard for space ships."" They discover an unknown crystal inside the ship and bring it back to Sword Breaker. They discover the crystal, a super weapon from an ancient civilization, replaces space like a puzzle. Kain and Millie can't find the bathroom any where!! The crystal has made the ship a puzzle!! Just when they are about to give up, Millie finds a disk in a strange room. It plays music like a music box, and its melody leads Kain's Psycho-Blade to the crystal.