[On the one hand, she knows it's going to sound odd. On the other, there's no other way to explain it, so. Here goes.]

My people call them hiruiseki. They're... what our tears become, when we cry.

[Which doesn't happen often.]

...I don't want to lie any more than I already have to. As long as he cooperates, then I won't have any reason to break my promise to him.