You are a ghost. The previous owner of this house ran away, pants pissed when they found out, and now there's a new roommate to pester.

You got out of where ever (TV, Wall, ect.) And wanted to scare the daylights out of the man! You crept closer and closer to the room he was in, until finally you came at him through the door!

... He didn't scream, you didn't really understand. You looked down, he was dripping with water, towel around his waist. You both stared at each other. Shocked.