Why Humiliation?

I have no idea, since I'm not a psychoanalyst. I think these are very complicated questions that we don't really know the answers to yet.

 

Internaliced feelings of inadequacy, or the sublimation of dominant tendencies, hard one really, not an easy answer, depends of many subtle aspects of the individual, but those two are main guides on those tendencies.

 

I have a theory about the development of kinks and fetishes. It's not exactly complete but I think it's on the right track. I could also just be overthinking it.

I don't think it's purely just random "novelty seeking" that brings people to develop strange kinks, certain people seem to go down certain tracks in certain genres. When you're watching porn, your mind is associating all of it with sexual arousal and orgasm. It's not just "oh look at that hot girl!". You are watching somebody else have sex with that hot girl. You are also fully aware of your position as a passive spectator.

There's a lot of secondary emotions and thoughts going on as you watch that you may not even be consciously aware of, beyond just the sexual excitement. Maybe you're a little jealous of the guy, maybe he makes you feel insecure about yourself. Maybe you kind of hate the girl, maybe she reminds you of those hot girls who have rejected you. Maybe you feel a little disgusted or guilty for watching them. Maybe you feel like a loser who can't get real sex.

As somebody gets desensitized to the rush of watching the sexual act itself, these secondary thoughts and emotions take over as the primary factor in sexual arousal. Somebody who feels a little jealous while watching regular porn is now only watching cuckold porn. Somebody who despises the girl gets into more violent, abusive porn. Somebody feeling a little disgusted gets into more disgusting porn, etc.

For example: Findom. I thought this was the weirdest thing ever. Guys are just giving money to girls in exchange for being insulted. That somehow gets them off. I had to think about it, I think these are guys who got into the habit of paying money in exchange for sexual arousal. Whether they bought porn, went to strip clubs, hired escorts or whatever. They were also painfully aware that not everybody has to pay to get sex and felt ashamed of their actions, on some level. Over time they ultimately wired their sex drives to view sexuality itself as merely the spending of money in exchange for feeling ashamed. Findom porn is just that.

So I think it's something like that. To answer the OP directly, somebody probably started off watching vanilla porn and unconsciously (or consciously to some degree) felt ashamed and humiliated for watching porn rather than getting the real thing. Over time that secondary thought became more and more thoroughly associated with arousal to the point that it displaced sex itself.