she grows a huge dick

when she looks down at her bare crotch, a tentacle starts to form where her pussy should be. it snakes out very far, and when it flops down it reachers her knees, and it doesn't seem very hard yet. once it reaches her knees, she concentrates again, forcing it to grow in thickness, which it does considerably. the final transformation consists of a huge cock and balls, and very small tits. the goo in her chest is moved elsewhere to make new or bigger body parts. her cock now easily extends 10 inches flaccid, and is about the thickness of a softball.

"I need to fuck you now for my tests to be complete." she says as she saunters over to him. her dick swaying even more than his when he moved. its thickness and length enthrall him, causing him to transfix his eyes to it while she moves closer. she holds it out for him to hold, which he does, not reluctantly or anything, just in awe of her size. it doesn't feel warm or cold, just slimy. he thinks it is good its slimy, because then he wouldn't have to put this thing down his throat to get it lubed up.

*gulp*"so you need this up my ass to complete your research?" he asks tentatively yet eagerly,

"yes. then you can go home if you want. but it's getting so lonely up here, and I need another person to keep me company. will you please stay?" she asked genuinely. it was true, after five years of no contact, she finally finds a lifeforms that she can connect with, on more than one level.she saw the size of his cock before, and easily figured out that he didn't have much of a sex life back home.

"o-ok, ill let you fuck my ass if you be gentle, I've never done this before." he said lying. he had shoved quite a good sized dildo up his ass at one point, easily 8 inches long and pretty thick. he only did it because he wondered if he was guy and if he should be the bottom. Patricks mentality was always try new things and if you like it keep doing it. he liked shoving things up his ass so he kept doing it, gradually getting to 8 inches. but this behemoth of a dick was going to be something else, he had never even thought a dick could be that big before today.

"I will, don't worry. just bend over the table for me." she turns him around and bends him over, his own massive dick pointed straight down. she wills her dick to harden to its full length, causing it to reach an unfathomable 17 inches, and impossibly thick. she licks her fingers and sticks a few of them up his ass to loosen him up. her spit also chemically causes his ass to looses, making this a lot more pleasurable for the both of them. after a bit of stretching, she takes her cock and lines the head up to his asshole and pushes.

Patrick shudders as he feels the size of her head against his bare ass. this feeling causes blood to rush to his face and his dick, making him get another raging boner. once he feels the head push in past his ring, he lets out a little gasp and a shudder. it's definitely bigger than the dildo he's practiced with. the alien continues to push in, and eventually the head rubs against his prostate, and Patricks mind explodes. he never thought please could exist like this. from this moment on he only wanted to get fucked by the aliens massive cock. she starts to thrust back and forth, only half her cock in his ass, and on every thrust in, her dick travels another inch inwards. slowly but surely she makes it all the way inside, and by that time, Patrick is a moaning mess, cumming everywhere, and panting very hard. while her balls tap into his, he knows she's finally bottomed out, and it dawns on him that she just shoved that huge dick up his ass in a matter of 2 minutes. he makes up his mind, he's never going back to earth, he's going to stay here on the ship with Zlob. while he's making up his mind, Zlob continues pumping his eager ass full of cockmeat. deep, full thrusts plunge into his ass, causing him to rock forward a little. Patrick braces himself on the table, trying not to move too much, he really wants to feel the powerful thrusts Zlob can give. eventually he starts to push back onto her dick, trying to feel as much of her as possible.