At Motherless there was an account called SixFootSevenSon. It was an amateur couple claiming to be a mom and son in a relationship. The account was deleted a long time ago and I've been looking for the videos ever since. I found three but I know there are at least two more because I remember the woman saying, "Don't just shove it in" at the beginning of one of them.

Here are the three I could find:
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