Yep. Party's a completely incorrigible rascal. No wonder Cooper is reminded of himself. Those are qualities he possesses and likes to see in others.

"No, she's almost twenty, I'll have you know." He looks a little offended. After all, he wasn't about to go chasing jailbait, being one of those creepy eternal teenage vampires that supernatural literature seems to adore. At the second question, he looks a lot more offended. He already knows he looks like a kid. The mirror tells him that every day of his life. "Don't be rude, pup. And I will have you know haven't been in school since World War Two. It's a little thing called a fake ID."