Dandadanx10

Momo Ayase is a high school girl who believes in ghosts but not aliens, while her fellow highschooler, Ken Takakura, whom Momo nicknames "Okarun", believes in aliens but not ghosts. In a bet to determine who is correct,Ben tennyson a boy who has a watch which turns him into aliens the two with ben going with momo decide to separately visit locations associated with both the extraterrestrial and the occult-Momo visiting the former, and Okarun visiting the latter. Momo is abducted by a group of aliens who accidentally unblock her chakras and ben using the omnitrix to help fight the aliens, enabling latent psychic abilities. Meanwhile, Okarun is possessed by a spirit who takes over his body. By using Momo's abilities and Okarun's possessed form and bens alien forms, they defeat the aliens together.

The rest of the story follows the three, as they team up with fellow students, friends, family, and new acquaintances to fight spirits and aliens; the overarching plot themes include retrieval of Okarun's penis and testicles (kintama) and the development of romantic feelings between Momo and Ben.