plurality
We didn't know what we were was unusual for autistics until only a few years ago! We knew some autistic people had worlds in their heads and assumed that also meant a detailed paracosm and inner life with people you couldn't get rid of in your head... then we became close friends with a lovely person with DID and had the '...wait... that's a Thing‽' realisation.
Under the DSM-V, we seem to fit the criteria for OSDD; under the ICD, we seem to fit the criteria for P-DID. We have not been professionally diagnosed and are not currently seeking such a diagnosis due to a combination of not feeling the need and mistrust of the psychiatric carceral system (including past experiences of psychiatric violence and medical abuse).
