The papa (a male supporter) I’m seeing in a monthly arrangement won’t reveal his background.

There probably isn’t any magic phrase that will suddenly make your papa (a male supporter) start talking freely about who he really is. Have you ever truly thought something through on your own? Instead of asking others so readily, try thinking it through for yourself. I have plenty I could say about your relationship with your papa, but it seems to me that thinking deeply about it is the only real solution. Isn’t the hint already contained in your question? For example, that you like him so much you don’t need an allowance, and that you want to know more about him. Personally, I think that at Universe Club, especially when a woman says she’s fine with “no allowance,” it’s the beginning of a tragedy—but I’ll refrain from making fun of that. What you can probably do is talk about yourself, if you want to know about the other person. That doesn’t necessarily mean sharing personal information. Rather, I think it means honestly expressing your feelings. I’m not sure whether it’s necessarily a good thing for a man and woman with an age gap to openly share their feelings in this kind of relationship. But if you want to know about him, why not first make a sincere effort to talk about yourself—including your feelings? In any case, give up on finding a magic phrase that will make your papa suddenly start talking freely about himself.

Don’t you think that’s because everyone has different circumstances and perspectives, and some people may feel nervous about it? If you become someone important enough to him that he feels comfortable revealing his identity, and the relationship develops into something serious, he may eventually open up about who he really is.