Today is Unification Day. This means that Mal is going around to look for fights in bars, Zoe's gone with him to keep him out of too much trouble, and for all Kaylee knows (or cares), Jayne's with them because he likes to punch things. Or maybe he's not with them. All she knows is that she doesn't plan to be there when they get back. She's got other things to try not to think about, and she'd prefer not to be disturbed by bloody noses and concussions and loud remonstrations and demands for cold packs.
She won't be able to avoid at least one of the things she's trying not to think about, it's clear: along with the onion rings and beer (and two empties) in front of her, she's got
a note from Dean Winchester, and she can't stop frowning at it.
Maybe Kaylee will write back when she's a little more sober and can figure out what the hell to say.