I wish there was a way to differentiate types of "adult" ratings. If you think you'll be doing more gore stuff, maybe put "guro" like a tag at the start in the same way you do with "commission?" Though maybe that's pointless since the whole thing was viewable from the thumbnail.
Edited to add: Apologies if it sounded like an accusation. I'm not saying the inability to somehow mark this as different from something that's just sexual is your fault. I did not mean to imply that you didn't follow posting guidelines or anything like that.
As for gore in the gallery, I think people would consider this different than the work you've done that has a zombie character or something similar. I don't know if reactions to those pieces were similar to this one. If they were the same, then I'm wrong. But if this one is getting a more negative response than those, then I think that would say this kind of gore is viewed differently.
Anyway, I could've articulated that more clearly when I first wrote this. If it means anything, I rated it in the middle since I greatly dislike the content, but I think you're a really great illustrator.