Lee Hajin, who is hiding his real name "Yuhan" and his past as a "recessive omega," now lives as a "beta." Without any family and burdened by debt, his daily life is plagued by catering to the whims of Jinseung, the son of the President of J Tech. One day, while meeting with a client, Hajin is reunited with his first love from high school, Seonghyeop. Seonghyeop, who once stayed at Hajin's house as the son of their chauffeur and a friend, has now become the CEO of a very large corporation. Even though 10 years have passed, the pheromones of the two are still strongly imprinted on each other. In their reversed relationship, Seonghyeop, determined to have Hajin who once left him, proposes a sexual partnership.