Some individuals can become excited at the sight of fresh blood.
In 1857, a 24-year old vine dresser named Ledger murdered a 12-year old girl in the woods. He admitted that he drank her blood, mutilated her genitals, tore out and ate part of her heart, and buried her remains. Ledger talked about this without any show of emotion or remorse, and when he was sentenced to death, he seemed just as indifferent.
There’s another case of a man who cut his arm for his wife to suck on before sex because it aroused her so much.
Another man dissected his victims and got so caught up in the gore that he trembled with the desire to wallow in the blood and consume it.
In most cases, men exhibit signs of blood lust. Before puberty, they may be excited in a sexual way by events that involve blood, such as an injury or ingestion of blood. During puberty, it may fuse with sexual fantasies.
Blood lust has compulsive components. People who suffer blood lust, may drink their own blood or the blood of others.