I wonder if this isn't just an aspect of the culture wars.... violence is good, sex is bad - an actual need to control women's sexuality and give that power to their husband/owners. Paypal's not out after war stories or murder mysteries, no they're after erotica.
Erotica provides pleasure to many women, giving them more independence, confidence, and satisfaction. Sexual gratification is an important factor in human health. Individuals should chose what they wish to consume, not moralists at a bank.
And for those who think that reading about rape or fucking a dog, snogging your step parent might make you want to actually go do it? Or that you reading it makes someone else thing you want to be raped?
Well the second of those concerns is way more important. That's another argument that blames the victim. "OH you got raped because of the way you dressed, where you went, what you read." NO. Actual rape in the world is a violence crime. People need to be educated that it's not okay, under any realistically conceivable circumstances to rape another person. Just because two people (or more) might be willing to role play a rape with a safe word, does not mean it's okay to rape them without a safe word.
To try to control what women wear, read, or where they go... to protect them.... is just a way to say that if they do get raped, it's really their fault, not the fault of their attacker.
Paypal needs to stop confusing fiction with reality.