Lilith

Lilith is the Mother of Demons, the creator of the entire Demon race.

Background
The first human woman to be created, that in another time, would come to be the mother of demons.

She is a special being that, despite being a demon of the highest rank that can be considered and evil god, she still has a semblance of 'goodness' in her.

Trivia

 * Aphrodite states that she never sleeps with demons since Lilith created them, suggesting that the two might have a grudge with each other.