Interesting question. I checked out Klarna and Adyen which seems to be the most popular in Europe right now. Adyen lists "Adult entertainment, websites & conte

Interesting question. I checked out Klarna and Adyen which seems to be the most popular in Europe right now. Adyen lists "Adult entertainment, websites & content (such as)" as not allowed. https://www.adyen.com/dam/jcr:47f292a9-c9e2-4a69-8592-2e15ffdc7e61/List-of-prohibited-and-restricted-products-and-services-June-2017.pdf https://www.adyen.com/dam/jcr:47f292a9-c9e2-4a69-8592-2e15ff... Klarna lists "Adult, sexual or pornographic products and services, including live web cam" as not allowed. https://cdn.klarna.com/1.0/shared/content/policy/ethic/en_gb/merchant.pdf https://cdn.klarna.com/1.0/shared/content/policy/ethic/en_gb... Both of them expand it more to cover everything possible around adult content and the like.