I remember reading a manga a while back that i would like to reread but I just can not remember the name of the series.

The premise from what I remember is that some people lost/sacrificed something special from within themselves to gain special powers. I remember that the guy on the cover of at least one of the volumes had a bone sticking out of his mouth like a farmer would a straw.

I know it is not a lot to go on but if anyone can help it would be much appreciated.