So I was reading about Shika deer, which is what Kaoori is, and apparently when they're alarmed or upset, instead of raising their tail, their... fur on their rear end fluffs up. So now it's an inside joke that Kaoori's butt fluff puffs up in alarm when she's upset.

If you can't read my handwriting, this is what it says:

Seond panel: *poof!*

Third Panel:
Wesker: You did that.. fluff thing again, you know..
Kaoori: I know, I KNOW!
*poof poof*