From Pluralpedia, the collaborative plurality dictionary
delusauxi (n., adj.)
Synonymsdelusion helper
Applies toheadmates
CoinerFae of the Vale

Delusauxi refers to a caretaker or internal self helper who completely or partially is and/or identifies as a system's delusion (whether they be an introject or just hold that specific delusion).

They act out or exhibit traits in line with that delusion (usually in a constructive or non-harmful way, but not always) to help the system cope and/or deal with the delusion. This is normally a voluntary role, but it can be done involuntarily.