I'd wanted to watch this already for a while, but hadn't gotten around to it until just now. Everything directed by Takashi Miike is awesome, so obviously, this is no exception. It's fucking awesome. No, it's not an intelligent type of a film, and it certainly doesn't have anything special in it, but it's still... well, magnificent, haha.
To be honest, based on how it started and what little I'd read about it beforehand, I expected it to be more of a black comedy than a thriller/slasher. I mean, it had a few comedic parts even late into the film, but well.
The ending left me a bit confused, though; so that one girl survived, even though she was thrown from the top of the roof after being hit so hard in the head that she practically passed out? I'm not saying unrealistic things are bad, but since the rest of the film was more or less "people die when they're killed"-sort of a thing, it was a bit strange.
But yeah, it was cool. It's not the best vaguely thriller/slasher/action/horror/black comedy film, but it would go on my top ten list of that type. All things considered, I'm gonna give it 80/100 and conclude that a little more (more what, I don't really know... just more something) would've made it a lot better.