shoulda put a ring on it
There’s a story behind it, obviously, and here’s the gist of it: they kind of... get married.
castle/beckett; m, ~7000 words. set just after 4x01 (rise) and goes au from there. spoilers up to that episode with the dog. just casually not even a little bit to do with any of the most recent couple of episodes.
here, if you dare (no seriously, it is so long, you may not want to).