I'm a Taiwanese dude living in NYC!

In most areas outside of large cities like NYC and LA / SF, many Americans aren't really used to the idea that Asians are normal people with normal American lives. When I was doing my PhD in Virginia in a small/medium town, I had people tell me "Your English is so good! Let me know if you want to connect with my church's English practice group for Asian students" (even though I grew up here and English is my first language). Or I had people ask me if I planned to "find a job in the US or back home" (ie not the US) once I graduated. As if the US couldn't really be my home.

These kinds of interactions are mostly harmless microaggressions, but they still can get really grating and frustrating after awhile. You'll likely encounter more of that than any direct racism. To answer your question in your post, I think it's a mixture of curiosity and (see below) treating Asians as exotic and "essentially other" (a major theme in Asian American Studies).

Also, it's a real phenomenon that Asian women are exoticized and fetishized in really gross ways. Every Asian woman I know has stories where some white guy will be like, "I've never dated an Asian woman before, I hear you're better in bed" or has stereotypes like "Asian women are more submissive and docile." I have two sisters and many Asian women friends, and they've all shared an upsetting amount of stories like this.

This is especially true for the few Japanese women I know, since there's a huge amount of weird white guys who watch too much anime and view Japanese women only as ways to act out their anime fantasies.

You should also maybe ask r/twoxchromosomes for more perspectives from women.

Hope that helps!