Sorry dude, its probably not going to happen. Out of the 15 or so women I have been with only one could bump & grind and take me balls deep, and she was able to take it all after just a little warm up. She was a tall curvy women, a lot of people on this site seem to disagree but larger women seem to have a easier time accommodating a large penis,at least thats been my experience anyway.
Try having her lay on you, with her back to your chest, If you are as big as you say you are shes gonna love it trust me

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