A deadly virus... Maybe inoculated by a small scratch/prick with a needle. The victim dies long after you "murdered" them, very hard to be linked to their death :D
Chainsaw! For the win! HAHAHAHAHA!
A big fat dick!
I would chop off the body and put it in the bath and finalize the ritual with acid.
It would want to be a polyethylene tub or you'll have a fine mess on your hands.
