One Week Locked In A House With...

So ur friend dares you to stay in her house by urself, while ur parents are out of town. You agree not knowing that secretly its a way to get you over your ex-Boy Friend, by locking you in the house with another person. It is one of the people from ur school. You get to the house and look around and then after settling in to watch ur fave show, you hear a boom and a muffled yell come from the closet down the hall. You decide to grab a knife and go check it out. When you open the door...........