In a trading hub city where various species intermingle, a homeless succubus by the name of Sophia is taken into custody by Aki, the son of a wealthy family. In exchange for shelter and sustenance, she works as his maid. Of course, in no matter of time, Sophia is head over heels for the diligent and kind young master... and she spends her days resisting the urge of her succubus instincts to "have her way with him!" Then one day, a robot named Aigis is employed as a new maid. Being a robot with no sense of "ethics," and having for some odd reason been programmed to act erotically, she violates the young master under the guise of "sex practice." Witnessing this, Sophia's instincts explode. If the robot is allowed, then certainly I must be too, right? RIGHT!?? She assails her beloved master and... Due to his duties as a master, Aki is resistant at first... but it doesn't take long for him to return to his usual earnest self, and simply enjoy the company of his two sexy maids as they pamper him and make lewd love together~