A part of [Identity][1], a physiological entity, is [Individuality][2], more precisely in this case [selfhood][3], means being seperate from others. For example two people who are Individual and have selfhood don't share thoughts except though actions.
Most nuro-typical people while awake can tell if another person is individual or part of themselves, for example being from there imagination.
Dream characters are sentient seeming entities in dreams, the terminology comes from lucid dreaming, although they also occur in non-lucid dreams. They appear to experience selfhood, whats more other…