Me too, Bauglir. I hate sitting on the ground. Painful as butts.
Yeah, just... sitting on the ground is kinda' painful and awkward (unless you find a nice nook in a hill that fits nice, or something along those lines. That can be really comfy.). Is why you don't do that. Floor is good -- provides flat surface. From there, bedding! If you want height, stack up a couple body pillows or somethin', maybe on top of a sturdy box. Sit. Back support, bedding throne against wall. Arm rest, blanket/pillow pile, probably against something with a little weight to it (box of books, wall, whatev'). You fit your environment to you and then roll around in it until it remembers the shape of your flesh. I can, have, and will again at some point in the future basically constructed scaled down chaise lounges out of spare bedding to lounge on.
Exceedingly comfortable.
Same sort of process that drives a cushion fort, except it's, like. A cushion couch/chair/table/whatever. The advantage over actual furniture is fitting (much easier and less expensive to make something you-shaped out of bedding than straight up furniture), space (your one pile of bedding probably takes up less space than a bed and can replace close to every piece of furniture in the house on demand), probably cost, and enjoyment (nesting is totes fun, yo'). Probably other stuff. Significant disadvantage is it's totally socially abnormal
Also a little more effort than premade furniture, I guess. Probably some other stuff.