I think blood doesn't improve erotic art. In many cases it is more of a downgrade.

Good guro art is unrealistic and cute. Real torture is never cute. Bondage porn as examble is also more sexy as a real kidnapping. Or the delish media cannibal vids are trashy on popose. Because it doesn't should look realistic.

Good erotic art is like cartoony fantasy. Even if a girl is cut in half or died. It alwals is more sexy, if they don't seeam to be in pain.

I have seen good pictures with blood… but not often.:)