Ask the Resident (Sex) Advisor
The Resident Sex Advisor answers sex-related questions from college students
You should ask her about it and find out exactly what the deal is and why she feels like she has to finish the job herself. Let her know that it makes you feel left out and you'd really like to help make her come. If she needs to be diddled just so to climax, have her demonstrate her technique and see if she can teach it to you. Be patient and practice, and see if you can get it right. If she needs convincing, just point out that if you can do the work, she can lay back and totally focus what she's feeling and relax as she reaches orgasm.
If it turns out that she absolutely can only get off while touching herself, you may have to settle for acting in a supporting role. If that's how it's going to be, negotiate the hand-off during sex so that your feelings don't get trampled. If she can tell you, "I'd like to touch myself now," that's a little kinder than just shoving you out of the way. See if there's something you can do to help while she masturbates herself, like sucking her tits, talking dirty to her, or just holding her. That way you'll at least feel a little more involved, and you might even start to enjoy watching her finger herself.
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