As a child, William touches a kelpie - the bloodthirsty spirit of Sleepy Lake - and miraculously escapes death, not even realizing how much this meeting will change his fate. Many years later, ghouls attack his home village. Trying to save his family, he himself finds himself trapped, but in the last moments of his life he receives from a stranger a rare gift - immortality. But in the demonic world of Sangomara, even help can turn into a curse. How can good-natured William now cope with the thirst for blood that he constantly experiences?