Hey there! First off, happy new year!

I am so sorry this happened to you. That is so disgusting and I'm sorry but I don't think sadistic behavior can be understood to anyone but the sadist. I agree with Valentina. It sounds like they were claiming you, but that's the only thing that I can gather from this. It doesn't matter if you didn't show them. He got mental gratification from that. They're not thinking of it as they're leaving proof of a crime. They're thinking of it as marking their property, so to speak. Abuse never makes sense to anyone but the abuser and this is an example of that. There's no reason why a human being would hurt another like this. I am very sorry. You sound like a very strong person and I wish you all the best!!