Hi im very new to nonmonogamy and in a fresh "monogamish" relationship (I am the exclusively romantic partner), I have a lot of jealousy to work through and I can't tell if I need to talk to my partner about this or not.

My partner has shared that my metamour is very into leaving marks, and my partner plans to get said marks from them, this makes me feel awful and terrible because ive never left my own and wanted to do it first, also find the idea of seeing my partner covered in markings that arent mine very uncomfortable and off-putting. Whats worse is the internet says hickies are a sign of "ownership", and I hate that. I don't know if i want to/can handle to see my partners "history" on his body right now, but I also don't want to like make him feel restricted by saying I'm not okay with it and needing to lay down a ground rule or something.