Intentional rape is typically about power, not sex. That's the vaaaaaaaaaaast majority.
IMO, that includes baby-rapers. They don't have power in an adult consensual relationship, & they have to have power over their victims, so they turn to children. Even those who can get it up with someone of equal status? It's not fulfilling to them. Because it's not about the sex. It's about being in power, and being in control. So the sick f*cks seek out victims they do have power over. That is only my opinion, however.
In the teeny tiny minority are lots and lots of various possibilities. So it can start to look really skewed when you see a list of a couple dozen situations versus one. But it's like saying most dogs have fur, and then list off all the hairless breeds. Just because there is a list of dogs without fur? Doesn't mean that most dogs, or even a lot, don't have fur. The vast majority of dogs have fur. The vast majority of rapists are about power. So I'm actually gonna list out the vaaaaaaaaaaast majority here first.
I forget who said it :
"Rape is about anger and control and violence. Sex is merely the weapon."
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Within that above group? There are a whole lot of different "types" of rapists. 4 main groups:
Power Reassurance - ("Gentleman Rapist", opportunity rapist).
Goal = to possess / own
((I call these ones low-self-esteem & poor-me-rapists. They need to be told you liked it, more often than not.))
Power Assertive - (Entitlement, Exploitative)
Goal = to possess / harm / capture-conquer-control
Anger Retaliatory - (Rage, Retaliation, Punishment)
Goal = Displaced anger. Often lethal.
Anger Excitation - (Sadistic)
Goal = Sexual gratification from victim's suffering. Very often lethal.
Then there are a whole lot of others, that are primarily group-based, not individual based:
Other - The goals here vary, as do methods & motivations... but whether it's a softening technique in torture & interrogation, or to humiliate one's enemies, or "breed them out" form of genocide, gang initiations, revenge (fictional example: when the girl with the dragon tattoo rapes her rapist) or a whole bunch of others / the list goes on... But they're still all about power.
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Blargh. I don't have the energy to list out all the minority cases where rape is not the intent / power and normal rape-rules and motivations don't apply... but they include things like small children acting out their own rapes*, teens* & young adults* -especially when drunk- who have crap communication with their partner (both sexes, especially, in this group) both start out consensual, then one changes their mind and the other doesn't listen. Freeze response, one partner doesn't want to but gives no indication so their partner has no idea. Forced rape ((I've been a part of that, blokes had no choice, I don't blame them. Correction. I don't blame all of them.)). Certain kinds of sex trafficking. Etc. Again. The above is just a partial list where rape / sexual assault happened, but it wasn't the intent.
* This by no means says that all of these examples rape was not the intent. There is a point at which a victim becomes an abuser (where that point is varies), and all 4 groups of serial rapists start somewhere... Often as adolescents. It's part of what makes child on child so damnably murky. Because for some there is no intent. And for some, there is.