She "like" the dik joke because the joke wasn't about having a threesome with them, it was about making fun of Chen who just failed with this pickup line. Even Jill would've found it funny in this situation, and she's probably the most "chick" of all the LI.
And come on, more like Lily? There's absolutely nothing coming from "Cinderella" that is close to Lily lol. Yes she is at the party, but she's also wearing the least provocative outfit of all the girls (or one of the least) AND wearing a mask (which doesn't conceal her identity at all, but it's still another way to cover herself).
I don't think that being at the panty party mean anything. Sally, Karen and a couple of other more timid/"chick" girls were there. And I'm pretty sure Maya would've been if she wasn't at Bella's instead.