Esper is a being of pure chaos. She doesn't possess a soul and is, by all account, completely insane. She acts on a whim for whatever soothes her interests. She tends to act on the side of evil because she finds it more enjoyable, but if evil is the norm or she finds a particular hero interesting, she has been known to assist them on their quest.

Esper is capable of powerful shadow magic. As long as shadows exist, so too does Esper. Her shadow magic allows her to creats chains of dark energy that she can use to transform and control others, but the true extent of her powers has yet to be seen.

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