Can't Stop Cursing You

At first, it seemed like an ordinary day at Yami High. But it wasn't.
A ringing cell phone and the splatter of blood marked the beginning of a deadly game.
The rules: Contractor Mikiya has thirty days to curse-kill thirty people or meet a fate worse than death.
On the other side, Curse-Breaker Saeyama must identify the killer without falling prey to one of Mikiya's curse-kills.
Only time will tell who will emerge victorious.