Remus and Spook have been playing like that ever since they met each other (after about 10 minutes of hissing and acting tough by Spook, Remus just had this look on his face of "chill out woman, I'm cool" ) Remus is a mellow cat but LOVES to play, and I think he likes flicking his tail in front of other kitties to get them to play too (he has done it for Pandora, Onyx and my MILs kitties on several occasions). He won't hesitate to smack a cat for being too rough though!