tackle bag
Any 'undesirable' female you manage to score with, one that you can practice all your moves on (and any dirty stuff) for when you manage to hook up with a hottie, the idea being that no matter how bad/dirty you were, you're not really looking to hook up this particular girl again
Guy 1: Mate, that chick you took home last night was nasty
Guy 2: I know, she was a tackle bag
Guy 2: I know, she was a tackle bag