Why do I have this hardcore fantasy/desire, what does it mean?

I have a sexual fantasy/experience I would like to have in real life, but it seems sort of out there and I'm wondering if others have a similar one and if they have been told what it means or where it comes from.

Fantasy:

I have a fuckbuddy. He's a bit rough, but I like it I'm definitely sub to him. He comes over, invites a couple questionable friends, they're drunk, they start making a mess of my place, eventually get rough with me, things get out of hand. They hold me, beat me up to the point of being dazed, truly injured, permanent marks, broken ribs, bloody nose, etc., tear my clothes off, forcibly and roughly rape me. Afterwards, as they're pulling themselves together, I'm half conscious on the floor, they take my money from my wallet and then piss on me while I lay there on the floor. Then they leave. I wake up untold amount of time later, in a pool of cold piss...

I deeply want this. I want the injury, the acute pain, the permanent marks, etc. I could see doing this once, waiting a few weeks, then wanting it again, and a few more times. I know this is all unhinged. Why do I want this? I even got a semi just writing this.