Lilith Mercer has lived outside of the walls all of her life in a land of exiled monsters. Inside of the walls, at the top of society are the Nephilim and then the humans. Banished outside are the demi-demons, cast out and forbidden to pass the walls to Inland. She has lived a cushy life despite the fact that she was raised behind the walls, as the daughter of Lord Mercer, the man who is pretty much the ruler of the demi-demon world, she is the future ruler and is as close as it gets to a princess in the outlands, until he forces her to take his place on a task to the inland where she'll be one of the only few demi-demons to enter the walls, and the first to enter the palace. Now, she must negotiate peace between the land of angels and their long time enemies, her home, while being the new guest of the royal family, and also dealing with the fact that in inland she is thought of as an abomination and is unwelcomed in a nephilim, nor human society.