If you don't like yaoi, then this is not a manga for you, and it is perfectly fine if this isn't your cup of tea. If you love yaoi, then you should definitely read it. Not only does this have a good plot line, but the romance involved with it allows the passionate love scenes to have a point and not be random smut. All the men are beautiful (as they should be in this type of manga!) and Yamane-sensei does not let you down for a good love scene between them. Ah, it's just so good! You have to go read it for yourself to see!
In order to protect his people from attacking demons, Prince Val uses a demonic sword and curses himself in the process. He leaves his kingdom to find a cure, and his search leads him to Hallwil, the person rumored to be the only one who knows how to break the curse. Hallwil agrees to help Val... for a price.