RE: Does your pet want to join you in the bathroom?
When I had cats, they almost always followed me whenever I went into the bathroom, and since that was where the cat litter box was; then they used their "bathroom" while I used mine. Then , I would always clean out the litter box, so it would not smell bad; so it actually worked out to being a good thing.
Cats will sometimes just follow people around just like dogs do. When I was growing up, we had several cats that had "adopted" us, and they were all outside cats because my mom would not let animals in the house.
We had a rental house just down the street a block or so, and when the house was empty, she and I would go down in the evening to work on cleaning it, and getting it ready for the next renter. We always walked down there, and always had a procession of the dogs and the cats following along behind us.
The dogs would trot right along beside of us, but the cats would go a ways, sit down and meow that they didn't want to walk anymore (or something ?) and then come bounding along to catch up with us again. Even though they grumbled, they always followed along whenever we walked down there.