While in the doggy style position, a man attempts to slip their penis into the woman's asshole without permission.
My girlfriend got really mad when I tried to throw her a backdoor slider last night.
When a man makes love to the crevice of a woman's butt by sliding his cock between her cheeks until he blows a romance explosion onto her back.
guy 1: "Dude I gave that bitch a backdoor slider last night!"
guy 2: "No way bro!"