I only have an "undying interest" (*chuckles*) in pathology at the moment - I have my BA in Anthropology and am considering post-graduate study in
medical or forensic anthropology, the last of which is almost undistinguishable from forensic pathology....but I've only had a few courses in my
undergradaute studies, so I'm by no means an expert, but I do have good resources to fall back on when drawing my conclusions....
The book I use the most is not the best, but it works: "Forensic Pathology," Second Edition - by Vincent and Dominick DiMaio - my prof had a friggin
awesome book with all color photos, but it was like $300...
At any rate...enough about me...

...the burn marks...
First off, that does look like a haematoma...but that means that a.) there is still blood in the body and b.) that some of the capillary veins did
collapse, or break - this also means that the victim didn't have blood clotting issues, so that kinda raises the bar on the question of where the
blood "went" - edges of the hole are what make me believe they are clearly electric burns...the edges of the hole are too smooth and symmetrical for
a stabbing, beating, shooting or other blunt force trauma
But then something else I thought of was the Brown Recluse spider...
That's a picture of a brown recluse bite....one which feeds off your internal flesh and basically decomposes your body very slowly....
As far as the mutilation of the genitalia - that happens alot in rapes....nipples cut off, the skinning of the pubic/perineal region, lacerations on
the anus, removal of organs, etc....
My opinion is that this was a homosexual rape - here's part of my evidence which comes from the book I mentioned above on page 444:
"Of interest are homosexual-related homicides. These tend to be more violent than their heterosexual counterparts. There is "overkill." The
victim is often nude and the number and extent of injuries on the body tend to be greater. The cause of death is usually stabbing, strangulation,
blunt force, or a combination of them all. The case might be extremely bizarre, with evidence of torture."
So if that were the case, I would think some form of taser baton or electric stun device that leaves a circular pattern could be responsible for the
markings and the mutilation was left to the rapist - After a few days of decay, he would look something like that....
Or maybe insead of an electric stunning device, the rapist was able to have this spider bite the victim against his own will, mutilate and rape him
while still conscious and then discard him....I dunno - there's lots of possibilites going off the photos and "report"