When Kwon Yi-soo’s mom marries her long-term boyfriend, of course Yi-soo’s happy for her. But is it too much to ask that his new stepbrother not be his ex-fuckbuddy who is ALSO his boss, Han Gangjin? Yi-soo is desperate to stop him from revealing their relationship to their parents, but Gangjin doesn’t have the same qualms. He hadn’t been happy about Yi-soo breaking things off, after all. So Gangjin offers him a deal: they resume seeing each other in exchange for their parents’ blissful married life. But can that be all that Gangjin wants…?