Bulking generally= bad in boxing.

If you can't take the punches, don't take them. Block them, slip them them, parry them. It's probably just me, but I really don't think being muscular helps you take punches THAT much better. It's something you usually either can or can't do. You're best bet for taking punches is learning how to take them, and learning how to avoid them, not making yourself bigger.

If I were you, I'd worry more about getting your skills down first, and getting in great shape, THEN worry about what weight class your gonna be in. There's plenty of time for bulking and cutting down the road.