This reminded me of a joke. A guy is mutilated in a car accident. Because his insurance was short the surgeon replaced one nut with a ball of titanium the other nut was made from wood. Years later he met the victim and asked how his life is going on. The dude reply his happily married with two children. The surgeon in amazement ask him what children. He replied that one child is the Terminator the other one is Pinocchio.
So his plumbing works fine, he's just shooting blanks? The Maulers sold him a lemon!! So he was totally right to screw them over the first chance he got. Too bad about him and Monster Girl but honestly if such things drove them apart it was likely that they were doomed from the start.