Remnant

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A remnant is a member of a system who is a remaining part of a former member of the system, specifically in the tense of a member that has no chance of ever coming back.

Remnants often hold a set of memories from that person, a specific emotion from that person from said person's point of view, or could view themselves as partially but not entirely that person.

The defining factor of a remnant is being all that remains or is left of the other headmate.

Related Terms
Remnants may also be ecliptives or otherwise appear in the aftermath of a member breaking.

Artifacts may be considered the fragment-analogue.