The Reason I Became an Omega

Having lived his whole life as a beta, Semin suddenly manifests as an omega. He's confused by the world that's turned upside down overnight, but happy that he can stand proudly beside Woojin, whom he's had a crush on for a long time. Then, he experiences his first heat cycle... * "You know what? If you keep touching your chest, it gets bigger." Woojin put both hands inside Semin's arms and pulled his chest together. Despite his efforts, Semin's lean chest remained flat. "Let's grow them big enough to rub my dick on." "Hng...!" Woojin pressed the tip of his finger on Semin's nipple. Semin twisted his waist at the ticklish sensation. "When we have a baby, milk will come out of here, r...