I would suggest you talk about it outside of the bedroom. In a neutral place and time. You said she's pretty open but she feels it is icky. Maybe if you would consider wearing a condom that might help. But as everyone else has said, don't push.

You might consider taking "baby steps". Maybe try just placing your finger there as you go down on her and massaging her anus. Don't push your finger in and of course make sure it is "lubed". A good time to do this would be as Stinger suggested. If she is comfortable with that, maybe you can try pushing your finger in at another time or she may even ask you to do so. The key being communication of course. Ask her, does it feel good, do you like it, do you want more. Listen to her and her body language. If you are not sure what her body is saying, ask her. And of course be prepared to stop if she ask you to.

Tigress

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