Chasing Flames

When Olivia shows up in the underworld, at first it seems that she was just unlucky in life. Sometimes bad decisions start to pile up and outweigh good deeds and at such a young age there wasn't time to reverse it.
But as time goes on Lucifer figures out pretty quickly that she's not meant to be down here. Mix-ups rarely happen and he's noticed that she's quite eager to stay. It doesn't help that he's found himself wanting her to stay.

Who is this girl and what is she hiding?