Gag 'n' Bag

An expression used to describe someone that you find physically attractive (enough to have sex with) but otherwise find replusive. Stems from the idea of gagging the person so that you can't hear the crap that comes out of their mouth, in order to increase your sense of pleasure when bagging (or sleeping with) them.

Kurtis is an arrogant, manipulative prick; talking to him for more than 5 minutes is overbearing which is too bad since he's such a hottie - he's a total gag 'n' bag.

or

A hot annoying/stupid chick that won't shut up would be considered a gag 'n' bag.