I’ve been seeing a generous (well-paying) papa for three months, but when he asked my real name at our first meeting, I gave him a fake one.

You could say that you’re not used to this kind of relationship (though I don’t know if that’s really true), and that you instinctively gave a false name because you thought that was what people did. You wanted to give your real name, but you missed the right moment and couldn’t bring yourself to say it. The trick is to bring it up as if you’re confessing something really serious—something with the impact of saying you’re breaking up or pregnant—and then reveal that it was just a false name. That way, they’ll think, “A false name? Oh, is that all?” Marika

I’ve never had a girl refuse to tell me her first name from the start, so this is just speculation, but I might let it slide with someone I’m currently seeing—though the atmosphere would probably become a little awkward. For one thing, it would make me start wondering whether anything else she’d told me was true. Also, my relationships have never been overly casual. I build a certain level of trust and give a corresponding allowance, so I think it would be a turnoff as well. Since the question mentioned it, I’m answering on the assumption that the papa is generous (well-paying). There’s no need to tell me her last name, but if she’s willing to share just her first name while keeping the kanji and other details private, I don’t think it would make that much difference. Normally, once you exchange LINE contacts, you can figure it out anyway. It’s not an absolute rule, but if her display name on LINE is intentionally vague, I start wondering about all sorts of things.

Everything except your name? If you’re telling the truth, then there’s really no reason to keep your name hidden anymore, is there? As Seattle-san said, I think they’d probably accept it if you came clean honestly.

After three months, if he tells you his name because he trusts you, I’d actually take that as a good sign. It should be fine.