I think I remmeber seeing it clearly enough at the scene where seymour summons anima to get rid of the fiends in the dome. I think it was Seymour's mother, or her soul anyways. That is what I think. Her soul is trapped in that picture on the necklace. This is what keeps anima's sanity. Dark Anima's is shattered because her spirit must have been broken and then the evil of the creature is set free to take over the body.