One doesn't always get perfectly clean and there can be a nasty perspiration coming from a butt crack. An oily sweaty slime can mess the sitting spot. I wipe major mess and then use a wash cloth to tidy up, but I still use a towel when I sit on my fabric furniture and often the wooden chairs, but it is mostly just me and DF sitting in the house.
I'm going to look further into this bidet idea, especially with a stack of towels. Bob, you have presented some very intriguing information, thank-you. Got me thinking.
This seems to me to conflict with composting toilets, which are popular here in the desert. They use no water, require no plumbing, no septic, can be used to grow things better. Now, with that, I'm back to a washcloth after paper. We use recycled T.P. From Trader Joes, which is at a competitive price. It breaks down biologically very well (I've been getting my septic system refurbished lately, first hand info).
DF has shown concern about my use of washcloths to finalize my cleansing. She was concerned that the crap wouldn't get out of the cloths, even with rinsing and washing. Do you wash in hot water, or bake towels in a dryer? I'm thinking stopping being so squeamish about a little left over shit that can be wiped and washed off, but I'm not the lady. I told her that I wasn't concerned, but my arguments were weak. I don't know that she is convinced and happy with my use of washcloths in that way. I squeeze out a washcloth after a shower and let it sit with some of the soap still in it, then use quarter sections and more of these for my butt. That way I'm not washing them in huge piles wasting water, time and effort.
Being nude does air out and dry much better than being clothed and cooped up. That oily slime will occur when wearing clothing which retards the airing out, much more than nude.
My use of bidets has had at times water dripping down my leg. When I pull the pants up, they get wet. I'm not always happy with the quality of the water there at those times, wondering which is rinse and which is clean water on my leg. Gotta stand up to dry my butt and the water dribbles down my leg. It has been kinda messy at times. MAybe, I'm just doing it wrong? So, I dislike bidets when wearing clothes, but they are not so bad when nude with a towel.
Jbee