Momo and Okarun set out on their latest adventure, traveling to a hot springs town home rented by Jiji, Momo's childhood friend and former crush, with the goal to solve the mystery surrounding his family.
Momo believes in ghosts, but not aliens. Okarun believes in aliens, but not ghosts. In their quests to prove each other wrong, they learn the shocking truth that both aliens and ghosts really exist and are out to get them.