Bastardised version of cashback. Used to describe the taking out of cash in order to go out and chase gash
Gentleman: Two cartons of um bongo and a packet of skittles please shopkeeper
Shopkeeper: Certainly sir, any gashback?
Gentleman: £20 please, I fancy a spot of wenching tonight and need some funds
Shopkeeper: Very good sir
Gashburger (n) A Vagina. The shape a vagina forms whilst bent over in a doggie style position during copulation. Or alternatively, bent over in a compromising doggie style position.
Gashburger. When a woman is crouched over touching her ankles during a sexual act, her pussy takes shape of a gashburger.
"Man, this babe has a hot looking gashburger, I could do her all night"!!
"Hey Steve, this chick I bumped uglies with last night, has the tightest gashburger ever"!!
Play on the type of naan bread 'peshwari naan'. Either used to comment on a bad situation. Or to signify that you are going to get some 'gash' that night.