Sub-sama, Jouzu ni Hizamazukemasuka?

University student Fuwa Hiroki is a closet sub. One day, he is assigned by his older brother, who runs a revenge agency, to a young Dom named Shishido Sen as his guard. "Damn, it's your first play? That's exciting." Hiroki is drowning in Shishido's non-stop commands. Hiroki thinks he will be forced to be in a play with Shishido, but Shishido does nothing, and Hiroki, unable to resist, begins to ask for commands himself. Hiroki intended to use Shishido just to release his sexual needs, but he finds himself becoming more and more attracted to Shishido's gentleness despite his usual cold personality... (Source: Houbunsha, translated) Note: Includes one extra chapter.