Read The Soul's Agent Storyline:
For as long as there have been people, there has been a fear of the dark. Mothers tell their children there isn't anything in the shadows that isn't there in the light.They are wrong.The reason humanity is afraid of the dark is because that's when demons come out to play. The ghosts that fight them can't come out until the sun goes down, either. And Soul's Agents, like Navi? They're just normal, boring people until the moon claims the sky.And then they aren't.Death allows lost souls one last chance. Fight with the Agents against demons and darkness and evil and they won't spend eternity roasting on a spit. It seems like an easy enough choice, but apparently roasting is easy and requires little effort, and fighting, well...Fighting is hard.Twenty-two year old Navi is an Agent, and she is good at what she does. Her only distraction is the boy who broke her heart four years ago—especially when the demons she hunts start hunting him, and she's the only one who can keep him alive.Pages of The Soul's Agent :