It's not that developed
I don't know why, but it seems like so many animators are making weak stories. Sadly this one is included. There really wasn't any animation or sound to complain about and it was executed in a well done manner but it seems that the golem was just a pointless addition to the story. A heartbroken girl writes on a golem that apparently reacts to hate. So apparently this golem was just sitting there waiting for some bitch to cry a river upon it? I dunno, it just seems a mechanized being known as a golem kinda entices the viewer to expect more than just some petty revenge. Quite frankly, if it were a demon, or a monster, or hell a more demonic looking golem I think I could believe it more but the golem didn't really look the part to me, but that's more of my personal taster than anything. I just think the set up was a bit much for such a little quote. Now, if you were trying to aim for the beginning of a series I think I could appreciate this more and be less of a critical asshole, but if it's just for lol's sake, then don't have it occur under such a weak premise.