When billionaire CEO and mafia boss Seo Kang-Joon notices a waitress who refuses to flatter wealthy customers, his curiosity becomes an obsession. He learns everything about Ava-except the one thing she never tells anyone. She has a daughter. On Episode 4, Kang-Joon secretly follows Ava home, intending only to see where she lives. Instead... A tiny girl opens the front door. Everything changes.