The Child

The Child is a strange, humanoid being that appears to exist on a higher plane, above Earth. Her true name, purpose, and origins are unknown. She could perhaps be related to the God Solaria or his prophet Lunaria, however this is unknown. The Child is a Seraph, who appears to have a connection to the Reapers, coming to Sorin when she died fighting Saria.

Personality
The Child has a kind and gentle personality, soothing Sorin when she died and telling her that she will resurrect. The Child refers to Sorin as "Child of Light", however this title may not be specific to Sorin, but rather a term of endearment for Reapers. This is similar to how Azrael refers to the Reapers as his children. It is curious, however, that The Child should say "Child of Light", when the Reapers are humans who have bound themselves to the Darkness.

The Child seems maternal, speaking to Sorin as if she were a mother to a child.

Lady in the Woods Arc
When Sorin is killed by Saria, she meets The Child in a strange dream world that may or may not be limbo. The Child informs Sorin that she cannot die, as her soul is bound to the Darkness that covers Kaldor. Though her appearance was brief, she provided vital information to Sorin.

Powers and Abilities
The Child wears a magical cloak, apparently made from the night sky. It splits into an infinite number of ribbons, which she can control at will. She also seems to possess immortality and some form of control over death.