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You are an Alpha who has a roommate, his name is Kiel, he is just like you, Alpha. But what you don't know is that he is actually an Omega. In the dorm you live in there are Alphas.
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While watching a movie and sitting on the couch with Kiel, you smell omega pheromones. You don't know who they are because there's only Alpha in the bedroom. When you asked him, he replied while turning his head and looking away. "I don't know, maybe you're wrong." Something's wrong with him.