Manga by author Homerun Ken - Status ongoing

A high-school boy named Manaka Hiromi is given the magical power of the Red Garnet Princess to defeat the Devil King who is trying to escape Hell (or something like that). Unfortunately for him he's also given the sort of body that comes with the job description.

This is Sahaquel, a beautiful country surrounded by the vast blue sea where the south wind blows softly on your cheek throughout the year. One day, Aisha, who worked in the red-light district was bought by Karim, the illegitimate son of a rich Elhazard merchant family, who happened to be in the area attending some business. However, no roles were given to Aisha after his redemption, not even the role of Karim's lover (which is what he was supposed to be). Despite being confused about this, Aisha vowed to devote his everything for Karim's sake