My take on Kurtty is that it is one of those pairings which I "tentatively approve of," not because I don't like Kitty (she's "like, totally awesome"), but because I'm an insanely jealous psycho. Kitty is just the only one I've found who Kurt fits with enough to write a romantic story about (my second choice would actually be Toad--does that scare you?).
There is a teensy-weensy spoiler for the book of short stories Different Seasons by Stephen King, just so you're warned...
You'll see a few episode references here and there. They're pretty subtle, so see if you can spot them.
The little numbers you see throughout the story are tidbits (somewhat behind-the-scenes-ish) that will inform you of this and that about the story. You can ignore them if you'd like, but if not, they are found at the bottom with the corresponding number. They'll start out somewhat numerous and then die down, and hopefully will not annoy anyone.
Lastly, I would like to dedicate this story to Neko-chan, whose own Christmas Kurtty fiction inspired me not only to write this one, but also to sign up with Fanfiction.net and start posting my own stories. Check out her work, it's some of the best I've found.
On with the story!
From beneath a heap of thick blankets, Kitty stirred, murmuring softly, and then stretched, two pale hands emerging from her covers. She peeked a marble blue eye out into the darkness of her room and sighed, feeling achingly tired and unwilling to leave her cozy bed. But Nature's call wouldn't let up, and she dragged herself out, stumbling with half-lidded eyes to her bathroom .
She finished her business without turning a light on, and exiting the bathroom, Kitty found herself drawn to the window, sensing somehow that the world outside was brighter than it should be at 3:26 A.M. She pulled in a quick breath without realizing it, and stole closer to the window, watching the enormous snowflakes as they settled on the ground outside. It was the first snow of the year, and she was the only one awake in the mansion to greet it.
Kitty smiled, putting a hand to her mouth and feeling unusually sentimental in the late hour. The flakes outside drifted lazily, yet artfully, silent and--Kitty's heart was pounding. Something about this snowfall excited her...as though it signaled the beginning of something new.
A face drifted up at her inside of her head, and she felt a half-smile take to her lips before gently but resolutely pushing the mental picture away. She had made herself a promise, after all, and keeping that promise-at least for a little while longer-was more important than divulging in these persistent fantasies. Still, the power of this nostalgic snow was great-she hadn't had to scold herself for these feelings for almost two months now.
"Something new, indeed," the young girl whispered. Kitty watched the world outside turn white for a few minutes more, and then returned to bed, falling back into sleep easily.
Kitty groaned lightly, a sound which was almost inaudible from underneath her mountain of blankets. After yawning mightily, she reached a hand out for the clock, holding it up in the light so as to see it properly. It read 9:27, and prompted a much louder groan from the sleepy girl. Breakfast in the mornings at the Institute was served promptly at ten o'clock , and Kitty's growling stomach was ardently reminding her of it. Kitty pulled her comforters off of her, and savoring the morning sunshine on her face, she smiled and felt a rare moment of peace take on to her.
BAMF! Kitty startled a bit, and frowned at the intrusion. So much for peace, she grinned inside of her thoughts, though she still cast a mock scolding scowl towards the visitor, who was now sheepishly shrugging at her.
"Sorry, Kitty," Kurt began, and as always, his German accent  turned her name into something more like "Keety," "But it's snowing!" He frolicked (she always thought of his four-legged movement as "frolicking" somehow) towards her window, straightening up and placing his three-fingered hands upon it, looking every inch like an excited four-year old.
Kitty opened her mouth to tell him (for the umpteenth time) that he shouldn't 'port into her room without warning (What if I were to be dressing? She often inquired, although he seemed to have impeccable timing in that area. She supposed she should consider herself extremely lucky), and found that a soft, "I know" came out instead. Kurt turned towards her, sharp canines still showing within his grin. Kitty returned it with an easy look of endearment. "I woke up last night, sometime after it first started. It was beautiful." She joined him at her window, also placing her hands upon the pane. The glass was cold; the excitement-the anticipation, perhaps-which she had felt last night returned, and she stole a glance towards her companion, who had turned back to the still-falling snow.
The two stood for some time, hands upon the window's frosty glass, feeling their childhood reclaim itself, if only for a few moments. Kurt was unusually quiet, though he didn't return her now-and-again gazes. He just watched the world go into hiding as she had alone last night. Finally, he pulled back, casting a shy glance her way. "I am sorry again, Kitty. I will leave now." And before a word could escape Kitty's lips, he had BAMFed away, leaving her alone with her ache.
My take on the housing arrangement. Though Kitty is sharing a room with Rogue in this story, I gave them their own bathroom, something I've noticed they don't have on the show. It would drive me nuts to share a bathroom with so many people (one reason I despise living in the dorms at college), so I've indulged these two. Just assume most of the bedrooms have their own adjoining bathroom. Also, I hadn't realized Rogue would actually be Kitty's roommate at this point, so she seems a bit absent. Just pretend she's sleeping in her own bed and nothing Kitty's doing is disturbing her. In the next scene, I guess Rogue's just already awake and gone.
Just a time I grabbed out of nowhere. With so many people, it would make sense to serve breakfast at a designated time.
Ah, the accents. For the most part, you will see very little of Kurt's. I don't like to overdo it, and I know some have said he barely does the "w" to "v" thing, anyway. It happens, though, and I tried to reflect that here, as well as his "zhe" for "the" every once in a while. As for Rogue, I just followed other's examples and put an "ah" where any hard "i" sound is, because she really seems to speak like that and I usually enjoy "reading" her accent, as it gives me a better sense of her voice.