A Sub just sent me a video of him putting a dildo inside an open wound?? How tf does someone even develop a kink like that

Context I’m an adult content creator, and I do a lot of dom, verbal, feet and pee content, I also have this special tier called “Owned: Cumslave” where I basically have a cumslave that I lock up in a chastity cage and who benefits from all the domination I can offer for a month, so I’m meant to work with people with extreme BDSM kinks, been doing it for a while, thought I’d seen everything. This one sub has been with me almost 2 months, always paid on time, took every degrading task like a champ. Yesterday he says he has a “special request” but wants to move off-platform (instant red flag, that’s how scams start). I told him no, everything stays on Fansly. He says “promise you won’t freak out” and drops a video. It’s him on cam, fresh deliberate cuts on his inner thigh, deep enough that it’s openly bleeding, and he’s slowly pushing a dildo in and out of one of the wounds while moaning my name and begging “please Sir, I want your Arab cock to do this to me instead.” I noped out instantly, reported him to Fansly, refunded his last renewal and blocked. Lost a good spender but holy fuck. No kinkshaming in general, and I myself enjoy BDSM to a certain extent but… wtf? how does someone’s brain even get to the point of sexualizing open wounds and blood like that? Is it self-harm + sex a known thing or did I just meet a genuine psychopath? Serious answers only, I’m still processing