The "Invisible Gods" protect humanity from the foul creatures they classify as demons. They spend their moments fighting and assuring that humans are unaware of these monsters but it all changes when the first half demon half human is introduced to these guardians of humanity. But one boy decides to train her and tries to convince her to join these Gods. Will this girl be able to fight and kill the demons to protect her human half or will she deny this opportunity so she doesn't eliminate her own kind?