In areas of BDSM like cnc(consensual non consent), dub-con(dubious consent), somnophilia(being aroused by someone who is asleep) or people that have preferences for hunter x prey dynamics in their sexual relationships. Things that can look like rape can be arousing to some groups of people for any number of reasons. The most important thing to these kinds of dynamics working healthily, however, are in the open and honest communication between the participating parties, and the aftercare shown to each respective of their role.
Its existence is neither good or bad on its own, since its ultimate use is for pleasure, as a lot of sex is these days.
If being pissed on and shat on can be a kink, then of course a rape kink can exist. That's essentially why non-con and dub-con content exists in the first place. Writers keep creating it because there is clearly an audience for it.
Rape is wrong, and I think that's also why people who have these fantasies or kinks probably don't talk about them openly. They know how they'll be perceived and don't want to be judged as disgusting or dangerous.
I don't have this fetish myself, but I think it's obvious that some people do.
At this point, I've mostly accepted that this kind of content is common in these spaces, so I generally don't comment on it. It would feel hypocritical for me to condemn it in one manhwa while excusing it in another, which is something I see people do all the time.
What I've learned is that a lot of people don't actually have a consistent understanding of consent. They'll call something rape when it's a character they dislike, but when it's their favorite character, suddenly it wasn't rape at all. Recently, I saw a manga where the ML rapes the FL, yet later when she is assaulted by a stranger, that assault is treated as horrific and the ML becomes protective of her. The double standard is hard to ignore. It's the same kind of hypocrisy I saw with Pearl Boy, where Dooshik organizes a gang rape and some readers were defending it because they felt the victim deserved revenge.
The whole topic is difficult to discuss because people are often inconsistent about it. That's one reason I usually stay out of these conversations unless someone is being blatantly hypocritical or the story itself acknowledges that what happened was rape.
For example, with Non Zero Sum, I think most people can agree that it isn't a love story.

So, ugh, I just asked because I didn’t know. Someone said, “At the end of the day r4p3 is highly wrong and bad but can also be consumed and enjoyed when reading for the kink and f3tish.” Does this kind of f3tish even exist? Like genuinely asking no troll to any readers