He calls her his "muse" and it's funny-
Because she muses about beating him with a hardcover book.
He calls her "Beckett" and she's placated-
Because it's rare respect from he who always has a comment that makes her want to bury her face in her hands.
He calls her "Kate" and it's disturbing-
Because at first, it's too familiar… and later, it fills her with inexplicable warmth.
He calls her his "muse" and it's infuriating-
Because Nikki Heat – ("Well, she is a little bit slutty!") – will never be her, and she sometimes doesn't know if that's a good thing.
Disclaimer: I own no bit of Castle (unless you could the DVDs and book?) – the show and characters belong to ABC.