[Rei's less interested in the proof as in the why he's telling her all this. Threats go over poorly with the goddess of flame and war, after all, even if she'll actively choose to diffuse any situation that'll involve a fight. Usagi apparently is rubbing off on her.

Naturally, though, his eyes tracking her hand don't go unnoticed and her smile shifts to something somewhat flippant.]

Interesting. I'm not as familiar with Mesopotamian lore as I probably should be, but I'll take you at your word. [She will, she's not lying.]

However, I believe I have something you want. And it looks like you have something I want too.