Foo Fighters

Foo Fighters, usually called F.F., is a colony of plankton given intelligence by a Stand disc in JoJo's Bizarre Adventure: Stone Ocean. After opposing Jolyne Cujoh, F.F. takes over the body of the deceased prisoner Atroe and joins her group.

Foo Fighters as a colony with a human identity

Curious, literal, and fiercely loyal, F.F. learns human identity through friendship rather than biology. Protecting memories and companions becomes more important than obeying Pucci.

Water, Atroe's body, and friendship with Jolyne

F.F. controls water-dependent plankton, repairs injuries, fires compressed fluid, and can divide or reshape the colony. The bond with Jolyne, Ermes, and Emporio gives the organism a personal self, while its death preserves that identity rather than allowing a replacement disc to define it.