P/K-tab mobility issues caused by weight loss

I like to lay on the floor in front of a sofa or ottoman stool and put both legs up on the sofa while lying on my back. I position my legs so they are bent at the knee with my butt close to the sofa. This allows full relaxation of my legs. You may try this and see if it helps you.

I'll have to go shopping for a memfoam body pillow or something to cushion myself on, but yeah.

You could buy man spanx and just cut out the back side. Another thing I like to use is a tail bone support pillow. It basically looks like a seat cushion but where your tailbone would be it's all cut out. I use that in a seated position and it allows the aneros free movement and also when I'm on my back I'm really skinny and don't really have an ass so the aneros is very close to touching the bed. If your legs are tiring out, you can drape a blanket across your bent knees when you're on your back. Then rest your feet on the ends of the blanket as you fold it under and kinda snug it up. It prevents your legs from wanting to fall outward as the blanket is held by your feet and keeps your knees in place and then allows you to completely relax your legs.

one of the Underworks bodysuits I've been wearing, there was an option for a zipper on the backside that I didn't take. I'll have to look at getting that one next time.