"Keys of the Poltergeist"
Cursed as a viral, sorcerous half-breed, Ayu Mayuki suffers through daily illnesses since birth. He becomes adopted by the Kosaki twins shortly after the disappearance of his father and the death of his mother. He agrees to go through their challenges and experiments to help discover the cure or he may not live a full life. Attending school, he handles acing through his classes, dealing with his rivals and other punks or the sudden, unexpected appearances of demons which thirsted for his blood. Why are these demons so attracted to him, and who could be summoning them? Will Ayu survive long enough until the cure has become discovered or will he be devoured alive?