Though.. You should really have made a story on the black cat instead of just ending it's story when one exits the fort. (I got the sense there were more to it's story than that with what it does and say when Atusa dies. So far the rewards that Sir Lora have given is pretty lame, they are source skill books that you can make, nothing special about them

With the cat you could have given the one it get attached to special abilities, like pounce (jump on someone and knock them down) and other abilities in addition to the ones the cat have when you summon it. The cat should just follow you as it does up to the point when you leave the fort instead of becoming a summon.