How do I tell my parents he’s coming to see me? (F26, M24)

How do I tell my parents the guy I met online is coming to see me?

I’m an adult in my own apartment. The man I met online is finally flying in to see me. He bought a one-way ticket so we don’t know how long he’ll be here for. He’s seriously considering moving to this state.

How do I tell my parents that I’m going to have someone I met online here with me? I know they’ll find out eventually since they sometimes randomly stop by to say hello (and just in case anything happens… I’d want them to know who I was with). They’re aware I’ve been talking to this guy, but I’m afraid they’ll try to talk me out of it or be really disappointed in me. I know I’m an adult that can make my own choices and do what I want, but I don’t want to make them worry or be disappointed in me.