I was a huge X-Men fan when I was younger, and around the time I was starting to masturbate, I usually fantasized about the women of the team. Every night, I'd jack off to another member, whether it was Jean, Storm, or Emma.

I remember reading an X-Men comic that showed several of the characters dead (in a Danger Room simulation). For some reason, I just started picturing the villains having sex with the corpses. It wasn't an especially graphic scene; they weren't bloodied or even that bruised, just limp and dead. I guess I just figured as long as they looked good they were still fuckable. I had this fantasy once or twice, never thought it was that weird or fucked up, then never payed any mind to it.

Years and years later, I discover paheal, still in it's early stages. I tended to look up a lot of Marvel and DC porn (since I had so much trouble finding any at the time). One of the earliest image results for Rogue and Ms. Marvel was a series of fantasy fights between them, where they constantly threaten to kill each other. By the end of the comic, Rogue kisses Ms. Marvel and sucks the life out of her, and the last panel has her teasingly straddling Ms. Marvel's now lifeless body while mocking her.
I thought it was so fucked up at the time, but I couldn't help but find the whole thing really hot. I kept convincing myself that I was only in it for the sexually-suggestive fight scenes and clothes-tearing, but I steadily realized that the added fatal element just made the whole scenario more erotic. Watching someone have sex before they inevitably died was this really thrilling prospect.

I steadily found myself drawn to porn depicting characters that were killed in their respective series (it was around this time I was really getting into Higurashi, a series that revolved around young, attractive characters around my age dying constantly, and it became a particularly favorite search of mine). However, I rarely sought out outright snuff porn, let alone guro, which did genuinely repulse me.

As the years went on though, I steadily got into more violent porn subjects. I was masturbating to rape porn almost every day by college. Inevitably, a few of these scenarios ended fairly darkly (Thanks, Nightmare Express), but I ended up just going with it, even enjoying it and seeking it out. Snuff soon became a huge fetish of mine.

Even just the mention, the mere hint that a character was going to be killed after the fucking was over was enough to make me enjoy the scenario more. I loved the pics from Alansmithee's "My Never-Ending Game of Hide and Seek" set, but it became so much better for me when translated versions of it came out revealing that the main character might have been killed at the end of it. When playing MythComplex's first game, I'd always, ALWAYS go straight for the scene where the minotaur piledrive-fucks Cassie, and it's explained afterwards in the Game Over screen that she was literally fucked to death when it's semen tore through her body.
I remember seeing a set of rape pics of May from Pokemon done by Gouguru that I really liked. On one comments section, an anon had accidentally misinterpreted a comment from the author on the original piece that these were the last pics he would draw of May because the thugs were going to kill her once they were done raping her. A simple mistranslation, but it was enough to make the entire image set that much more erotic for me, to the point I did my own dialogue edits for the set.

I've since gotten into slightly harder stuff, but honestly, it's mainly simple snuff that I'm into, though it has to be after a rape. I've started to really get into decapitations and headfucking though. It's just brutal enough without being too gory for me. Also, any scenarios involving a character being defeated in a fight, humiliated through rape, and then further humiliated with an execution or fatality. Executions in general really do it for me.