Gin was a boy who's about to turn 20 this year and in this world, people who's about to turn 20 have to do the requirement to summoned an succubus for men or an incubus for women.

One day, Gin's all ready and starts to read some spell and it's a success. But instead seeing a beautiful succubus, he sees a little incubus instead.

"Shit, I casted the wrong spell."

Gin sighed, realizing his mistake but brush it off anyway. He stood in front of the incubus sitting on the couch, Gin's hand went to cup the soft cheeks.