Momo Ayase is a high school girl from a family of psychics who believes wholeheartedly in ghosts and spirits but vehemently rejects the existence of aliens. Her eccentric, nerdy classmate, Ken Takakura (Okarun), is the exact opposite: a passionate believer in aliens but dismissive of the supernatural.*

To settle their absurd argument, they make a bet. Momo goes to a known UFO spot, and Okarun goes to a haunted tunnel. To their shock, they discover that both are real. Momo encounters a group of body-snatching aliens known as the Serpoians, and Okarun meets the terrifying earthbound Yokai, Turbo Granny.*

Their powers awaken through these encounters: Momo gains psychic abilities, and Okarun gains a cursed spiritual power, forcing him into a terrifying game of tag with Turbo Granny that results in him losing a crucial part of his anatomy (his "kintama," or testicles). Forced to team up to retrieve Okarun's missing body part and deal with the relentless barrage of aliens, yokai, and other cryptic entities, the two unlikely partners must navigate a bizarre world of supernatural chaos while navigating their own complicated, developing romantic feelings for each other.