I think though,

keep your finger out of it for now, or — if she's reeeeally into the first part — after a little while of that you can ask if she likes Digital Underground, and then if she's like "Humpty Dance?" you can be like "I want to stick my finger in your ass," 'cause she definitely didn't get the joke, and you want to be sure before you tickle someone's ivories (I don't even know, anymore, what we're talking about) that they know what you're about to do and are on board with it. Because, penetration, you know? I mean, do you want a chick to stick her finger up your ass without making sure that's something you're into first? Also, I am 100% asking you that question, please someone answer that question! But (butt) yeah, I think if you just ease into it, give her a chance to communicate in one way or another that she's into it or not, and then go with that, then you're all set.
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