Shoujo/Josei 2

How is it possible she lived so long and doesn't have a way to lie down where only she would get dirtied rather than the sheets? There are certain positions that allow that once you don't move. As someone with the heaviest of heavy flows and younger, I feel she's weird for sitting on the ground like that with a heavy flow and not dirtying the ground and then sitting on him in that position and thinking she won't mess up his pants or anything, i.e. if she actually HAS a heavy flow like what Ik.