Okay boys, here are the down and dirty things you need to know to get her to let you give it to her "back there." Most women are probably like me, they have had guys begging them to let them do it, and a few have tried it once or twice to discover that it is painful. Pain is not a requirement of anal, and that is something that people need to know. Now boys, if your girl has had one of these experiences, she is going to be even more reluctant to let you do it. My biggest suggestion is to be patient. Don't ask her while you're in bed, and hope that she'll turn around and offer it up to you like a birthday present. It probably won't happen unless she has done it before and liked it.
And she can like it, all it requires is a little sensitivity on your part, and a willingness to follow a few simple directions. I will dispense my advice on this subject now.
1. Tell her that you fantasize about it, but don't ask her to do it-- not yet. Hearing you talk about it will put thoughts in her head without making her feel pressured or nervous.
2. Many of you will not like this one, but here it is: ask her to do it to you. I'm not suggesting you buy a strap-on or anything, although if you are into it, great-- I'm talking about asking her to just put her finger up there. Tell her how great it feels, and how much you love it.
Before you let her do this to you, allow me a few personal preference related suggestions. Wash yourself well, and make sure you don't need to "drop the kids off at the pool" anytime soon. This is a messy and unpleasant discovery for any woman (okay, most women). Furthermore, buy yourself an anal douche, if you want one a bit more cheaply (anytime it is marketed as a sex product the price shoots up a thousand fold), you can go to your local pharmacy and buy an enema kit or bag. This will ensure that your colon is empty and clean before you proceed. I know, an unpleasant thought, but let's be real here for a moment: we all know what comes out of there, don't we?
3. Use a lot of lubrication, your choice here, but ensure that you are using enough. Then ask her to insert her finger in your ass. Don't say it like that. "Darling, would you do me the courtesy of inserting your digit into my rectum?" won't do you, her, or the mood any good. Say something sexy; "I want to feel your finger inside me," works well for me, it isn't crass, but doesn't leave a lot to the imagination.