Well you know you're doing a good job when your girl is trying to make you cum :thumbsup: But how have you never rimmed a girl? I can understand not getting anal, but you don't really need permission to rim her. You just start with licking her pussy and make your licks just a little too long or start a little too low (depending on which direction your coming from), and if she doesn't protest, with a little bit of patience as you slowly go further, pretty soon you can just focus on her asshole and your rimming her. And if she does protest, which I doubt she will, you can always say it was unintentional or that you enjoy her taste so much you just got caught up in it, kept going, and didn't realize how far you'd gone.