I have a one year old, medium sized, mixed female dog. She's obsessed with licking her anus and her vagina. Sometimes one, sometimes the other. She doesn't skoot across the floor or have any gross discharges coming out of either of them. I'm unsure if she has a problem or if she is just doing it out of boredom or becoming obsessed with it. It's grossing me out and I want to know how to get her to stop. Thanks in advance.

She may have an infection or need her anal glands expressed

Is she spayed? If not something serious could be going on like pyometra.

You should take her to your vet. Any behavior that isn't normal should really be looked at by a vet