I think the spreading of the chest skin kinda tips this towards guro, unless the hypothetical arranger figures it looks less "uck" this way than laying them down.
If there weren't any "pretty flowers" in this, I think it would be tagged automatically as "guro", so... Just because it's beautiful, that doesn't take away the fact that it is indeed macabre. So I think the guro tag should be applied, but that's just me. It should have a "mutilation" tag at the very least. Is there even a mutilation tag?