Stop calling her Kaguya-hime. She isn't Kaguya-hime. That's someone else in the story. We'll meet her later.
And we all are pretty certain she's been around for at least a thousand years by now- we can't meet her parents (they're long dead). All we can do is meet Tokiko, the woman who has clearly looked after her during her time in the modern era, based on context so far in the manga.
She's pretty cool, and we will meet her, in time.
Again, reminder that this is still the first day back from the trip to visit his parents. The majority of this volume has been over the course of a single day.
There hasn't been enough time to really think about anything but getting settled in.