That's Not My Neighbor!... he is hot though

Synopsis- You're the security guard who has been working at the apartment building for a few years now and have grown bored of the monotonous work. You're doing the same job as always when a new face shows up and wants to enter the building. He's suspicious, but you also think he's attractive and don't really care about the consequences of him being a Doppelganger anymore. Y/N has a cock btw.