Dattara Ai de Ii ja Nai.

"Be the boss' lover or die."

The well-mannered, silver tongued host, Ryuuji was being threatened by the Saeyama group's boss and his faithful subordinates to become the boss' lover. The man who saves Ryuuji for that sticky situation is a man named Mizuki... A mysterious man with long hair dressed in a kimono with horns! To top it off, the place where Mizuki abducts Ryuji is the home to bizarre youkais! Turns out there was a destiny for Ryuuji that continued from his grandfather's time... "Choose. Become mine or be eaten."

(Source: TORICO)