This series started out very strong. A girl who has been able to see ghosts for all her life and has accepted that as a fact finds out on her 15th birthday that her mother had made a deal with a demon for it to possess the girls body when she turns 15. She is supposed to be this bastion of Yin energy which in this particular universe feeds Demons and they grow stronger.
First few chapters fast introduces us to the Girl called Ah-ryoung who is a pretty much loner in her school because she is often seen talking alone to the air. Unlike her,
most people cant see demons or ghosts so she seems like a lunatic for babbling away alone. She is an interesting character as she is fairly strong for a person who has been alone for most of her life. She has hard time adjusting to her new life with a demon stalking her and trying to take over her body but its soon revealed that the power within the girl is far too much for this particular demon to out do and they both are left in the akward situation of being bound together by a contract.
The demon is called Nachal who is trying to take over Ah-ryoung's body because that is the only way he thinks he can avoid going to hell. The story has not progressed (at the time of writing) long enough for it to be revealed who this Nachal actually is or why he is still roaming the earth but some flashbacks have been shown where he is standing victorious on a battlefield. He seems cold on the outside but at times he is defending Ah-ryoung from danger. He says that he only does it so he can one day take over her body but i reckon he is growing fond of Ah-ryoung's kind nature. We will have to wait and see.
There are many demons, gods and otherwordly creatures in this story and one of these revealed that every spirit or a demon left in the world is hold there because he or she has a grudge about something and it must be dealt with before one can leave the earth. There are many of these demons introduced and all of them look unique and posses interesting powers. Each one of the following their own plan trying to get something which is out of their reach.
I hope that this series gain popularity so it can continue long enough for all of these characters to have a chance to grow as a character more than just be left out like i have seen happening to many characters in many other shows. There might be a good manga here if the writer dosent screw up with the characters too much.
If you like demons, fighting and a little bit of romance on the side i highly recommend start reading this now as its not progressed too many chapters yet (23 chapters on mangareader.net)
Dont read this manga if you are looking for a decent romance story. Its not that major in this one and i can recommend reading something better for you if you like romance, go read "Kiss Yori mo Hayaku " One of my favorites that.