Dandadan

Momo Ayase is a high school girl who believes in ghosts but not aliens, while her classmate Okarun believes in aliens but not ghosts. In a bet to determine who's correct, the two decide to separately visit locations associated with both the occult and the supernatural—Ayase visiting the former and the boy visiting the latter. When the two reach their respective places it turns out that they were half-right, both aliens and ghosts do exist.