plural system

Noun

 * 1) A group of multiple identities, headmates, or alters sharing a body.
 * 2) A person with dissociative identity disorder or another related dissociative disorder, such as P-DID, OSDD-1, or UDD, among others.
 * 1) A person with dissociative identity disorder or another related dissociative disorder, such as P-DID, OSDD-1, or UDD, among others.

Usage notes
Frequently shortened to just system in situations where the context is obvious. Some, but not all, tulpamancers consider themselves and their tulpa(s) to be a plural systems.