Exclusivity in Relationships

Hello! Good morning / afternoon wherever you are!

I just have a quick question from my fellow gay bros (i was really closeted growing up and still don’t know much about gay culture and what’s normal)

From the gay men I have talked to, it seems like relationships are often a bit more… open? Is this really the case? Like, am I going to be an odd one out for wanting to be fully exclusive with someone?

Thank you!!!