I know it's supposed to be at an angle but why does his thigh look like a ham roast

Zero_00 said:

I know it's supposed to be at an angle but why does his thigh look like a ham roast

Because it's not well-drawn, nor shaded properly.
The knee should be up higher. The outline of the thigh should have been moved inward ever so slightly from both sides to narrow its thickness and the shading on the bottom should go higher up, similar to how Ryou-ouki's thigh is, on the bed.

I like Ryou-ouki's pose and expression a lot. She's calm and happily enjoying the sex.
Not sure what her right had is doing. My guess is that she's suppose to gently have her had on Tenchi's head, but with the thumb still visible, it feels like his head is further back than that. If his jawline had overlapped the thumb, that would've been so perfect, as if she was gently touching the side of his head affectionately.

That's pretty much the only things I would've changed. Lumpy thigh and hand on face.