Bastet

Bastet is a "child", or soul, that you can summon to fight your way through the world of Destiny Child.

Profile
A girl who feared death turned to a demon in hopes of finally escaping it. The resulting Child, born from her pactmaker's desire to be protected from everything, took the name Bastet, after the Egyptian guardian goddess.

Since Bastet doesn't trust anyone else, she never reveals herself, even to her allies. Her specialty is hiding inside other people's shadows; how in the world she does that is anybody's guess.

Children
It should be noted that in this case, the use of "child" does not mean the character is a child. Like all the other summons in this game, "child" simply refers to the soul that is being summoned.