It all started out slowly, maybe even innocently; the Doctor couldn't tell at first. Soon, however, Rose's changes became more and more evident and her motives more and more suspicious. One week, curtains appeared on the windows. The next, knickknacks began to line the kitchen shelves. Everything was getting a bit too domestic for the Doctor...so he decided to start fighting back.
It was the day after the Tardis disembarked from Felspoon that Rose spotted a little hula girl doll on the console. The war had begun. Soon after, tablecloths and fresh daisies somehow found themselves on every table the Tardis had. A week later, the Doctor came across some fuzzy dice. Rose countered by bringing Jackie on board for a tour.
The breaking point came when the Doctor bought Billy the Big Mouth Bass - a plastic fish that once mounted on the wall started singing whenever someone would walk by. When Rose first passed it, she nearly jumped out of her skin.
Enough was enough. She found the doctor under the grating next to the console, having followed the distinct clanking noises that only came when the Doctor was "fixing" something. Leaning back against one of the coral-like fixtures, she interrupted his tinkering.
"A fish?" the companion said, raising her eyebrow, half-annoyed, half hopelessly bemused. The Doctor peered out from under the grating.
"A, uh...a bigmouth bass. Micropterus salmoides, you see." He twiddled with his sonic screwdriver while talking. "Actually a member of the Sunfish family. Not a bass at all really..." Placing the device down, he cautiously climbed up from his hiding place, not exactly looking at her. "Actually, there's a planet where their voice-boxes have evolved enough to the point where they actually *can* sing. Though that one doesn't sound anything like them," he babbled, trying to get out of the situation. "The singing fish, they're called. Only ones who can. Although I'll admit, not the most original of names. Maybe we can call them the opera fish, or the enormously elongated vocal chords fish, or even the-"
Striding up, Rose pressed her lips against the Doctor's. Taken aback, the Doctor's mind went blank; what to do, where to put his hands, how to kiss like he should all fell out of his head. All that was left was his lips parting just enough to let her in. 903 years old and he had never had a kiss like this one. He brushed his hands over her stomach, finally having them rest at her hips as he pressed into her more, finally finding his own. Rose's tongue glided softly against the Doctor's, and he reciprocated, teasing hers possessively. A burning sensation bubbled up inside him as he felt Rose's hands in his hair, and he deepened the kiss even more, bringing their bodies together.
As they let go and air filtered back into their lungs, his eyes searched hers. Rose's breath hitched and his mind whispered softly, "I could get used to domestic."