I don't know who Kermode is and never really heard of "Hormonal Horror" till now, but I could definitely see where he's coming from.
After all, it is (a slasher movie) about a bunch of teenage guys who want to get with a particular girl from school. Definitely a lot of typical teenage behaviour in this one: truth or dare games, exploring sex, bullying, ...
So yeah, it's a good example of that genre, much more so than it is an example of the horror genre at large.