I've only met... I guess you could call them "defectors" from the moon, and they're nice enough. It's a pure land, though, and from what I hear those that live there are very concerned with keeping it that way.

[Which means driving off anyone else, except under the most extreme circumstance.]

They launched a full-scale invasion of Gensokyo not too long ago because of a revenge plot. It was a rough time, Chang'e was involved, it turns out that someone from there has a bizarre power that twists the truth or reality or something... They're not a people I'm interested in extended contact with on their terms.