I have a cat who wants to pretty much be in my room 24/7 and I have to "kick him out" when it is time for Snickers (the bunny) to have floor time. Milo (cat) does paw at Snickers through the cage bars but never claws out, I think he is mostly curious about him. That being said, I would never, ever trust a cat (declawed or not) around a rabbit without supervision. Cats can still bite, and even without claws they can still hunt. It would take very little for kitty to pounce the rabbit, pin it, and be done with it - and their bites, should a rabbit survive, contain a LOT of bacteria. My niece was bitten by an elderly cat and hospitalized due to all the bacteria in the mouth of the cat. So even without claws, do not assume the danger is gone, I am afraid.
There has only been 1 time in which my cat and rabbit have been loose together and it was when my grandfather let my cat back in my room without knocking first while Snickers was out in my room. They both ran under the bed but luckily only looked at eachother like "What are you?!" and I was able to chase my cat out of the room and put my rabbit back in the cage. I probably over-reacted but I was very scared, my heart was racing! I was terrified my cat would hurt him.
So in a nutshell, proceed with caution and do not leave them unsupervised at ANY time. Your kitty and rabbit may learn to live together and tolerate one another's presence - and they may even become buddies - but they should never be left without supervision. Cats react to sudden movements, which rabbits are so prone to making. Your kitty won't be thinking "he is family" when instincts kick in, and he may even be trying to play. But kitties play rough and make eachother scream when they play, let alone add in the fact that bunnies are much more fragile and not suited for that play. So even if your cat doesn't mean to, he could potentially hurt the bunny.
Good luck!
