Scary on some!!! It depends on the person, if they are skinny and tall then it would be looking good, but if they are fat, I think its better if they stick to normal casual looks.
It depends on your definition of hardxcore punk. fishnets, eyeliner, converse, black and red, spikey hair totally attractive...chain pants, high buckled boots, fishnet shirts long stringy hair, cherry lipstick that turns down at the corners...i think that guys might find you more attractive as a friend, less of a love interest.
They would think that they are hardcore punk! The guy might think its sexy or tough or brave. It depends on the guy. Preppy guys would think you are tough and maybe a tomboy.. but once again it depends on the guy.