First, a good lubricant, preferably a water-based fisting, and plenty of it. Second, when you push yourself up to the knot with your weight, slowly create pressure on the asshole to open (it takes a little time) and she slowly pushes it into the asshole, at first it will hurt a little and it will be strange, but each time it gets better and better. You are obviously on the transitional border, I was also with the dildo in the picture, I tried several times, it didn't work and I thought it couldn't go any further, then I lay on my back, leaned it on my ass and slowly held it with my hand and increased the pressure. As I increased the pressure, I moved it a little left, right, up and down, and suddenly it found its way. The first time he smashed my ass to a new dimension, it hurt and it would take me a week to recover, but that's why every subsequent penetration was better and better. In the end, I realized that what was holding me back the most was fear, and since then I've been enjoying every new dimension. Your ass as well as mine and everyone else's can easily expand up to 5 inches in diameter without consequence if you gradually increase in size. The only problem could be if your dildo is too soft, and if you have someone, it would be best if he stuck it in you.
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