Alright, so I've just brought home a hyper little five month kitten, Grimalkin. She stayed in my bedroom for three days, so that my resident cat, Marmaduke (seven year orange fluff ball) could get used to her. He was a mix of extreme fear and curiousity...for the first day, he wouldn't even go upstairs. He just stayed in a dark corner, completely petrified. Seriously, when I felt him, he was completely rigid and stiff, not showing any response. For the next few days, he staked out my bedroom door. I put his food dish beside the door, but he refused to eat out of it until I moved it back three feet.
Grim was so completely bold, trying to grab Marm under the door even while he was in full hiss. It was a seriously terrifying sound too, something I've never heard from him! But I don't think he was being aggressive, I think he was just afraid. His ears never went back, and his back never arched. He remained sitting, and even slept curled up beside the door.
On the third night, Grim escaped. She was always rushing to get out, but this time she managed to slip past me. Marm, of course, was right there waiting. I was about to completely freak out and grab her, until I saw that they were sniffing noses quite calmly. Marm let out on last hiss (his final one. No more after that), but was very eagerly sniffing her all over. After 10 seconds, she lost interested and ran off to explore the house.
On the first day of Grim running freely, Marm followed her everywhere. It was like he was in a trance; he was just fascinated with her! She largely ignored him, except for a couple faux-rushes, where she started to play and then chickened out. He wanted to play, though. He kept flopping onto his side, swatting at the air, and purring. She didn't take the invitation. That night, they both slept on my bed, Grim on my chest and Marm on my feet. I was woken up in the middle of the night by a loud yowl...Grim had finally summoned up the courage to play, and was chasing my poor tabby (who, at 17 pounds, is over four times her size) around my room. I was ready to leap in and save him, until I realized that he was quite enjoying this. He leapt onto my bed and began batting at her from above, ears fully forward.
It is now the second day of Grim running free, and the fifth day altogether. Marmaduke has stopped following her everywhere, but still pays her full attention whenever they're in the same room. He let her steal his bed, and his food, and use his litterbox. She's a cheeky little thing! And, when I got her still for a couple minutes (she was lolling around in my lap, purring), he came over and started licking her all over. I was completely surprised....it's not uncommon for Marm to try to groom Bailey, my gigantic dog, but I never thought he would warm up to Grim so quickly. He's still quite intimidated by her, but he loves her!
Grim is a different story. He's tried since then to come up and lick her, and, while she often touches noses with him, she won't let him get that close. When he tries grooming her, she swats at him (but with retracted claws, and never quite touching). She doesn't seem to be interested in him at all.
TL;DR - Start here ;]
So, that's what I want advice on: how can I get Grim to warm up to Marmaduke? It's a bit sad to see her giving him the cold shoulder, and I'm worried that this disinterest will be permanent. They've only been together five days, so I should probably give them some more time, but is there anything I can do in the meantime to nudge Grimalkin into being more affectionate?
Sorry for the poor picture quality. These were all snapped pretty quickly with my phone