The Frost system is a Neurogenic system of fluctuating count, with 6-7 headmates in the fronting rotation at any given time. Frost has no host, and never did.
Members of the Frost system have full memory sharing and continuity, but instead each absorb separate feelings pertaining to a memory or experience. Nobody in the system has any intention of seeking a diagnosis, as Plurality does not cause any issues or discomfort for them.
Frost tends to be more active on the associated Discord server than on the wiki, is one of the moderators there, and can be easily contacted there.