My cats are always hanging out in the bathroom. Paizly's favorite window to sit in is in the bathroom. Not sure why since you can't really see anything past the shrub that covers the window, but she loves it.
Jax always jumps on the counter when I go to get ready to shower at night. He usually wants a massage then I have to turn the water on for him to get a drink. And he has discovered the tub too. I'll find him just sitting in there watching us go by. Silly boy!

I've found both of them just hanging out on the toilet lid, or for a while (I think it was rats/mice under the house) Jax would hang out behind the toilet. He doesn't do that much anymore since we've set traps under the house.

I have gotten out of the shower several times to find all four "kids" in the bathroom with me. They have the entire house to be in, but they must be in the tiny bathroom with me.