If someone shares that they installed a bidet, I thinking asking which model is a pretty reasonable followup.
I was thinking that, too, before I bought the $38 Amazon special referenced in other comments below. To get heated water, I'd have to run wiring and an outlet, and...oh, screw it, try it without the heat and if it's not acceptable I'll buy a better one and do the electrical work.
phhhhht, it's fine, and I'm glad I didn't go to the trouble. It's a nice-to-have, but not worth tearing apart drywall to run wiring, IMO. OTOH, if you have an outlet in a convient-to-reach location (e. g., under the toilet), then YOLO.
"Old work" electrical boxes are specifically designed to be added without tearing apart the drywall (other than making a clean hole, obviously). The lack of romex staples over a fished wire in such scenarios is typically acceptable by code. Now if the bathroom isn't immediately above a basement or immediately below an attic, it might indeed be impossible to avoid some demo.
It looks kinda like this but with a curvier handle:
https://www.amazon.com/Handheld-Toilet-Adjustable-Pressure-F...
You don't need a fancy motorized electric thing (I don't trust cleaning all those little nozzles and angles). I started using this after I stayed with a Muslim friend in Morocco years ago. I had no choice but learn, and now I'm hooked. My partner thinks it is gross, tho. /shrugs/
But how is it gross to rinse a dirty part of your body with potable water? I think it's grosser to use the bathroom for solid waste and expect rubbing it off with tissue paper is going to result in an equally clean outcome compared to rinsing with water.
https://smile.amazon.com/gp/product/B00A0RHSJO/ref=ppx_yo_dt...
My wife still refuses to use it, even when we were still scrambling to find TP.
No idea how they do it in Japan.