The guy who’s only after my body—

I’m the one who asked the previous question. We’ve been messaging every day since then. He looks young for a man in his 40s, and I like how confident he is. However, he calls me by my first name without any honorific and seems to think I’m his girlfriend. On the day we last met, he said, “Let’s get married,” and, “We’re officially dating as of today.” Of course, I assumed he was joking. He’s not a bad person, so I’d like to stay close as friends. Am I being selfish?