Foist

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A Foist is a headmate that, when fronting or co-conscious, will manifest as a hallucination in specific circumstances or situations. The manifested hallucination can be of any type.

The manifested hallucination is unintentional and/or automatic.

In the specific circumstances or situations where the hallucination appears, for example, playing a video game, the hallucination may only appear within the video game or may only appear as a hallucination relating to it.

Related Terms
Imposition refers to intentional hallucinations of headmates.

Projection refers to when a system experiences having a headmate appear outside of their physical body, intentional or non-intentional.