Green’s Dictionary of Slang

(US campus) a male term for an allegedly promiscuous woman.

1975		G. Underwood ‘Razorback Sl.’ in AS L:1/2 62: lust dog n Passionate female, usually of low reputation.
1989		H. Rawson Dict. of Invective (1991) 44: Instead they resorted to such euphemisms as doggess, dog’s lady, lady dog, lust dog, puppy’s mama (or mother), she dog, and slut pup.