I'm mostly happy with this one. In typical hunyuan fashion, it doesn't always listen to directions, but most of the time you end up with a decent video. The previews were generated at 0.9 strength.

The main part of the prompt is:

A woman is straddling a man and having ??? with him. She bounces up and down on top of the man
Depending on the angle of the camera, you can either directly see the genitals or not. You can add this to your prompt to try to get them to show up:

You can see the woman bouncing up and down on the man's ????? penis.
You can prompt for different angles:

{The view is from the front and at a 45 degree angle.|The view is from the side|The view is POV}
Some of the training data had the woman facing away from the camera, which you can try, but the 2 people are positioned weirdly more often than not when doing so.

By default, the woman's knees will probably be pointed down, so if you want more of a squatting position with her knees up, you can prompt for that this way:

She is squatting with her knees raised