Eric sat on his bed, dumbfounded. He couldn't believe what he was hearing and seeing. He'd never thought some kinky fun with the Chronivac would turn into this, would leave his girlfriend a sex-crazed creature so depraved that she wanted to turn him into his own rat's cock and ride him forever.
"Catch," said Lisa suddenly, dumping Tomtom into his lap. "H-hey!" he shouted, instinctively moving to lessen the shock to the poor rodent. Tomtom was really in no danger, but it had startled Eric enough to give her the chance to turn and type some commands into the accursed Chronivac.
He wanted to yell for her to stop, to smash the damned machine, to yank her away, anything...but there was something about the way she looked, standing there, bent over the keyboard...fuzzy ass pointed toward him, tail flicking back and forth in satisfaction...her delicate pussy protruding slightly between her legs, in a way he'd never noticed before. The fur on her legs was matted there, and he found himself slightly jealous that he hadn't been the cause. God, even now he wanted to be inside her.
Tomtom squirmed in his lap, annoyed at being brushed aside by the bulge of Eric's hardening cock. The sensation jolted him out of his reverie. What was he thinking?! He had to escape!
But in the next instant, several things happened that would make that difficult.
First was the sharp >tic< of the enter key being pressed, with an air of finality.
Second, he found himself with a faceful of hot, musky fur, pinned to his bed by 200 lbs. of rattus norvegicus. Tomtom had grown to the size of a bear and was crushing the breath out of him. "...Help..." he groaned. He could faintly hear Lisa's laughter, but muffled it sounded more like rodent chittering.
Tomtom rolled forward off of him and Eric gasped for air. The giant rat took a few steps and turned to face him, nose wiggling slightly, sitting upright on his haunches. Lisa crept up beside him in an embrace, running a hand through his pectoral fur. He gazed down at his mate and put an arm around her.
"He was confused the first time I made him this size, but I think he's used to it now," she said with a toothy grin. She reached down and pawed at his crotch to coax his erection from its sheath. "He wasn't quite this big before, but this should make it easier for him to stay inside of you. Might be less comfortable for you, but I know you're willing to do what it takes for the sake of our future, right?"
As an attentive pet owner, Eric had seen his rat's dick a few times before, but hadn't exactly lingered on it. The bestial thing was gigantic now, shaped like a long, narrow cone, still glistening from his mother's juices. The oblong furry balls below it were massive. He was almost sitting on them.
That's going to be me, Eric thought in horror. That alien-looking cock is going to be the entirety of my existence from now on unless I do something, and fast.
Lisa could see the wheels spinning in his head. "D'aww," she said in mock concern. "You're not quite into it yet. Darn! I should've fast-tracked the mental changes. Listen, if you struggle, this could go very bad for you. Tomtom already knows the plan" -- the big rat nodded -- "and he can restrain you long enough for me to make you cooperate. But I'd rather not have to do that and just get to watch the show, so play nice, okay?"
Eric noted the two of them were blocking the door, and there was no way he'd be able to escape through the window. He didn't know the effective range of the Chronivac, but if she'd started changing him as he pulled in the driveway, it was far enough. There might be a chance, though...
Lisa pointed down and traced a circle in the air with a clawed finger. "Pants off, face down, ass up. Let's get this underway already."