Apparently his beloved ancient cat died (awhile ago, but still!) Nathan told both Ellen and The View ladies about a cat he inherited with his house. The cat was old and decrepit and he was led to believe wouldn’t live long. Then it lived a really, really long time. And despite not liking cats or wanting a cat, Nathan ended up not only letting the cat move in with him, but he rescued it from a raccoon, built it steps up to his bed and some crazy contraption to help it walk.
This was all just more fuel for the fire of the Awesomeness that is Nathan Fillion (oh and apparently he has a new cat now so that’s happy.)
Also, you should be watching Castle and helping Nathan become the Big Bright Shiny Star he is destined to be.