Alyssa: We did the season premiere [of "Charmed"] and we had a trained dog... Paige, Rose McGowan's character, gets a job walking dogs, as a dog walker, and so we're doing a scene and all of a sudden out of nowhere, the dog [a bulldog] is in the scene and I hear the trainer, off to the side, go 'Hop her, Hurley! Hop her! Hop her!' and this dog takes a running leap to Rose McGowan's leg, and just starts humping, and humping, and humping,
[Milano helpfully demonstrates in her chair] and Rose kicks the -
Leno: I'm sorry, how did the dog do it again?
[Joking] I'm sorry, I missed it.
Alyssa: The best part was that Rose kicked the dog off and the dog was still humping the air, with this face on...
["I know the feeling," Leno added. "I think every guy knows that face!" "The dog," Milano explained, "actually turns into a man, played by Joe Millionaire (Evan Marriott)."]