Jihan, a beta who has been close to Yoonseo, the younger sibling next-door since childhood, unexpectedly enters into a relationship with him. Soon after, Jihan receives the sudden news of his pregnancy and discovers that he has manifested as an Omega. It becomes apparent that Yoonseo, a Dominant Alpha, is the father of the child. However, in order to secure a future for Yoonseo, who is still a college student, Jihan decides to terminate the pregnancy. Nevertheless, Yoonseo openly reveals that both Jihan's pregnancy and the change in traits were part of his own scheme, stating… "Hyung has always meant to be my Omega. You have always been mine."