A woman so ugly, use of a bag over her head, your own head (in case hers falls of) and, to prevent lasting psychological damage, your dog's head is required.
A woman uglier than a two bagger. One bag for her head to stop you seeing her ugly face. A second bag for your headjust in case her bag falls off. A third bag containing Viagra so that you can still get it up in case the other bags fall off!
Tracey was such an ugly cow that she was a three bagger. One bag to cover her ugly mug, another to cover mine in case hers fell off and another full of Viagra so that I'd get hard!
An extremely unattractive lady. A reference to the practice of putting a bag over the head of an ugly lady while having sex with her. A three bagger is so ugly she requires a bag for her, a bag for you and a bag for the guy looking in thru the window.
It's like a two-bagger, (a paper bag for her head, and a paper bag for your head in case hers falls off), but you get a third paper bag to be sick into, in case both bags fall off
She's got a hot car booty look about her body, but her messed up face makes her a definite three bagger.