1.) Willow is laid back, calm, very relaxed, but has a short fuse. All you have to do is ruffle her back when she's sleeping and she'll give you a smack and she'll hate you for a few hours. Touch her belly when she's standing next to a window (or simply just standing anywhere) and she'll kick you with her back legs and try to bite. When strangers come over, she watches them like a hawk and if they try to touch her, she gives them an expertly-timed swipe so that they bleed with just the slightest effort (it always looks like her nails are contracted and she's simply swiping the air, so we're all shocked when the person's thumb bleeds). Yet when you're not pissing her off, she's a major sweetie who craves attention. But in order to see that side of Willow, you have to ignore her for much of the day. She's very independent and will want to choose for herself when she wants attention.
2.) Buffy is a wild, crazy firecracker. She came to use when she was 4 weeks old and Willow, who was happy to sleep before then, was forced to play "tag" every day until Buffy mellowed out (though she still demands playtime, at least she seems considerate of the fact that Willow needs to sleep too). She loves attention, will purr if you look at her and simply just touch her nose (then she'll purr and will pause with confusion if you don't continue). All you have to do is move your hands really quick and she's ready to play. She'll play with anything, from your shirt sleeve to a milk cap strip. One of her favorite games is when I shove my hand deep into my sleeve and start whipping the flap around. She'll come running and will give my arm a hug (to stop the shaking?) and will gnaw on my knuckles, if she can find them. She's very carefree and LOVES attention (when she was younger, she would panic if you left her alone in a room, though now she realizes it's okay to sleep by herself). She's very opinionated, sassy, and bossy (Willow doesn't have a life anymore: she just obeys Buffy's every command, though she seems happy to do so, strangely). My sister loves to hold Buffy up and stare into her eyes, and that pisses Buffy off, so Buffy will mrowwwllll for a few seconds, then will give my sister a smack across the cheek if my sister doesn't look away. My sister gets a big kick out of it and, I admit, I do too. She's just so predictable: pick her up, look her in the eyes, and she'll smack you across the face. She only did it to me, once, when I wanted to try it, but it took a long time for her to do it. She never hits me or bites me unless it's out of play or I'm clipping her nails, but I believe it's 'cause I'm her "human momma," (Willow raised her in the cat-world, but I took care of her when she originally came here and Buffy would panic the most if it was me who left her alone in a room. Sometimes I'd be walking somewhere in the house, go through a doorway, and a few seconds later a family member would see Buffy running hot on my trail, refusing to leave me). I dread the day that Buffy dies but, if she stays away from cars and other miscellaneous dangers in the many times that she escapes from the house, it won't be for another 15 years. I can't stand to think of the day that Willow dies either, because Buffy and Willow are like Siegfried and Roy, but without the magic. If you talk about Willow, you have to talk about Buffy too, and vise versa. Plus both cats love each other and I'm not sure what they'd do if the other "disappears" after 15 years together.