I liked it though...

It is hot horror in a sense of horror. This is drama, very sad, extremely well played drama about loneliness and childhood of abuse. Main actor Zabrecky is brilliant in my opinion. I could really feel for him, even to connect in some way. This is not a horror, if you expect buckets of blood and depravity, you will be disappointed. This is a sad drama with some small elements of horror. But it is a good movie, especially since Zabrecky almost alone brought whole movie.
It so happened that I watched Decay and Nina Forever on same weekend. Though Nina forever has higher score, I almost gave up on that movie it was so incredibly boring. I barely watched it till the end and I regret losing 100 minutes of my life on it.
On the other hand, I had lower expectations on Decay but movie was actually better (scores on imbd are not really giving it justice) and holds attention much better. There is no sexy young a$$ to hold your attention like in Nina but real acting. So I would give it high score.