At what point of seeing someone are you expected to be exclusive and stop having casual sex with other people?

I met someone online and things took off, there’s a lot of chemistry and we’ve developed some feelings for each other, we’ve known each other for almost a year now but things have been flirty for the past six months. We made plans to meet this summer once the quarantine is lifted off and I’ve been celibate just to be safe, but is there an expectation for me to be so? We haven’t really discussed exclusively. I’ve honestly been too scared too bring it up in case he thinks I’m too attached or something. I don’t really date very often do I’m not sure what the expectations are usually. He has joked around once about asking someone else out (he didn’t) to gauge a reaction out of me before so it made me assume he thought him seeing other people would upset or freak me out, therefore it wasn’t something he’d do.

I’m probably over thinking this.