Phone your parents and tell them that you really don't fit in and don't belong there. Tell them from now on you will keep your room clean, pick up after yourself, take out the garbage, help out in the kitchen and anything else you can think of. Put out food/water for the pets, etc. If they let you come back home, be sure to do what you said you'd do. If that doesn't work, then tell them you're afraid someone is gonna hurt your private-parts. Then when you get home, tell them you just made it up.