When In-Seob receives the shocking diagnosis from the doctor, his life suddenly spirals out of control . He is an Omega - how can he possibly tell his family? Desperate and unable to think clearly, he seeks refuge in a nearby store. A drink, he thinks, maybe that will calm his nerves. But what starts as harmless drinking quickly turns into a nightmare. He encounters a mysterious man with with broad shoulders , whom he recklessly invites over in his drunk state. But what happens next? His memory blurs, and when he wakes up, he is in a strange room, naked and with no explanation. Beside him, the man from the night before lies sleeping. Panic sets in as he hurriedly gathers his scattered clothes. What happened last night? And who is this man?