Hiding his real name 'Yoohan' and his past recessive 'omega' trait, Lee Hajin now lives as a beta. It has become his daily life to please Jinseung, the son of J-Tech's CEO, while paying a debt and living without a family. One day, Hajin, reunited with Sunghyeop, his first love in high school at a supposed meeting place with a client. Sunghyeop, the son of a driver who lived and slept at Hajin's house in the past, became the CEO of a large company. Even after 10 years, the two are still clearly imprinted on each other's pheromones. Sunghyeop then, proposes a sex partner to monopolize Hajin, who left him.