Butterfly(2002)

Ishikawa Ginji is a young man who happens to hate any kind of business related to 'the other side', such as ghosts, superstitions or the occult. His despise for the matter is such, that he can quickly break up any girl if they show any interest in matters such as lucky charms or any kind of future reading.

One day, while he was self pondering about his life while ruining a date on a whim, he is suddenly kissed by an elementary school girl go goes by the name "Ageha", stating that she will use him to "wipe out every ghost in the world". While the sex appeal of an elementary school kid kiss was not enough to turn Ginji to her side, the fact that she "bought him" by paying a huge debt that he had acquired seems to work quite efficiently.