I'm an Incubus who's No Good at What He Does

Tasuku's never had any problems finding people to hook up with. One night, he sees a frumpy-looking young man, Mitsu, being picked on by a drunk. He helps Mitsu, but Mitsu can barely stand. Unable to leave him on the street, he takes Mitsu home only to be told the shocking truth. Mitsu is an incubus