Actually it's 18 volumes and 7 chapters. The last chapter is chapter 90 came out 09.2006. So in all it will probably be 19 volumes of HM in total.
Dude there are only 14 volumes out and I think 14 is the last volume. I say 14 volumes are out because Akita Shoten says 14 volumes are out.
Every dead body that is not exterminated becomes one of them. It gets up and kills! The people it kills get up and kill!