Cats can be real creeps. One of their commonly-reported creepy behaviors is the habit of following their owners to the bathroom. Why do cats do this?
Why Does My Cat Follow Me To The Bathroom?
It turns out that some cats are big fans of following their owners everywhere. Their reasons for following you to the bathroom are probably similar to their reasons for following you in general. Though veterinarians and scientists haven't come to any definitive conclusion, they have several theories that might explain why your cat is so keen on following you to the bathroom.
Veterinarian Dr. Kathryn Primm writes that cats may feel vulnerable without you. Cats are predators, but they are also prey, and they are aware of that. Since you are a source of safety and comfort, they might feel less safe when you're behind closed doors, and prefer to accompany you to the bathroom, where they may continue to take advantage of the safety you provide.
Dr. Primm also posits that curiosity plays a role in a cat's bathroom-following habits (like it does with many cat behaviors). Cats are visual hunters, and like to use their vision to keep track of where things are. Dr. Primm points out that when you close the door to the bathroom, you are doing something mysterious behind it, and your cat may feel compelled to get to the bottom of this.
You're a captive audience.
Cats learn quickly that when a human is seated in the bathroom, they can't go anywhere. Plus, most bathrooms have a counter conveniently located at cat-petting level. This is a great setup for cats, as you have to pet them on their terms, and you cannot leave.
Cats just like you.
A lot of cat behaviors can be explained by the fact that they simply like you. Additionally, domestic cats' lives are fairly uneventful, and you're probably the most entertaining thing in the room most of the time. Your cat may want to follow you to the bathroom to see what entertaining thing you do next. What if you do something really funny in there and they miss it?
Cats demand privacy when they have to use the litter box, but they refuse to grant us the same courtesy. Unfortunately, it's just one of the many indignities of owning a cat.