A shock absorber is a guy that you take around with you to meet girls. The shock absorber's primary job is to entertain the ugly girls that are friends with hot girls, thus 'absorbing' the 'shock' of the situation as you now have a cockblock-free chance to hit on the hot girls. The shock absorber usually already is in a serious relationship or is gay.......or both.
"Hey Steve Watson, wanna be my shock absorber this summer?"
"So, this girl in a wheelchair came up to me. But luckily my shock absorber, Steve Watson, took care of her."
"Who wants a moustache ride?..No not you, ugly girl. You can have one from my shock absorber, Steve Watson"