Ryouma who works as a “boyfriend for rent” has a special constitution: He can see other people’s emotions. One day, he meets a psychology student, Aoyama, who has a “black haze” around him. Curious about this unknown emotion, Ryouma tries to get closer to Aoyama. But when Aoyama finds out about his ability, Ryouma is asked to be part of a psychology experiment?! Still curious about the “black haze,” Ryouma agrees to it for a while. What will happen in these ‘experiments?’ What is this “black haze?” Will Ryouma finally fall in love?