A cute little story! I like the subversion at the end, with Meg siding with the humans instead of Diamond. It's nice she wants, on some level, to support her partner! I think I'm more on Diamond's side, myself . . .

One nitpick: "Mini-balrog" normally has a hyphen in the middle.

—doctorlit reads the Christmas interlude on Christmas

I’m not sure if we’ve seen anything of Meg before, (though I do recall her getting a wiki page) but this was delightful. “Christmas from the perspective of a demon” is an inherently funny and original idea, and you pulled it very well.

—Ls, practicing Christian