Go with her

The two of you are in step as you leave the union, back towards your rooms. Your fingers twist around, exploring Samantha's insides. Meanwhile, the two of you make idle conversation.

"So Sam, when was the last time you actually got hit by the craving?" You figure that finding out more about this world will help you enjoy it. Your right to every lady's ass seems fairly easy to understand, but the actual implementation of your other change might be a little more complex.

"Well, like most girls I wake up at least once a night with it." Your eyes widen in surprise before you remember you're supposed to already know this and hastily calm yourself. "Luckily me and Cara are so in sync - by the time I realise it's hit she's already got three fingers in me and her nipple in my face. So to answer your question, I think it was about four in the morning today. During the day yesterday I only got it twice; the national average but I'm a randy girl!" She bumps her hip into you and return the favour with the addition of a third finger inside her.

What confuses you most is this Cara: as far as you know, you've never met anyone called that. You hesitantly ask about her.

"Uh, my roommate Cara?" Samantha would never agree to have a roommate. She hated sharing a room with her sister growing up, and she told you once one of her favourite things about moving out was having a room to herself.

"How on Earth did they convince you to share?"

"That's sick, man. Maybe you're into that desperation thing but don't just bring it up out of nowhere." Her response confuses you more, and she elaborates.

"You're supposed to sleep, like, seven-to-nine hours a day right? And most girls crave about three times every twenty four hours, so one of them is likely to come up while they're asleep. I can't remember the exact current laws, but it's at least negligence to have a girl sleep in a room without another girl there. My parents were lucky; they got two daughters in a row. Neither of us had to be sent to one of those houses for single daughters, or be **** to move in with another family. And of course all female accommodation here has to be for at least two girls, and there's a system for if one of you wants to sleep somewhere else even just for one night."

You never considered all these implications when you asked for these changes. Society has warped itself to fulfil your fantasies, but just how much had to be altered shocks you. As you walk up the stairs in your block you pull your fingers out of Samantha's tight hole and give a her a reassuring squeeze on one cheek. All thoughts of morality fly out of your head however, since the door to Samantha's room just flew open with a resounding crash.

In the doorway is a girl you've never seen before in your life. She has shining, solid black hair down nearly to her tits, which are clearly visible. All she is wearing is a single white sock and a pair of pale pink panties around her thighs. Her boobs are more than a handful each; far more than Samantha carries. Her face is flushed and sweaty, and her eyes are wild, manic, searching. You glance around: no doors have opened despite the noise and the one other person in the corridor, a guy you know by sight if just by living in the same building, just continues to walk on as if nothing is happening.

A breathy gasp - "Sam!" - draws your attention back. Sam, now also looking a bit flush, calmly walks towards the girl. She puts her hands either side of the girl's face and is immediately kissing her ferociously. A moan escapes the girl's lips through Samantha's and her eyes close, her body visibly relaxing. Samantha takes purposeful steps forwards, leading the girl into the room. You follow.

It seems bigger than you remember. That's probably to make space for the double bed and second desk, reminding you of the girl Cara. Thinking about it, this almost naked girl is probably her.

The twosome have fallen onto the bed, Samantha still holding Cara's face tightly. Every movement of her lips and tongue creates a sticky, erotic sound that brings you to full hardness in a matter of moments. Cara's hands are exploring her partner's body. Clothes are flying off Sam even while her erogenous zones are stimulated. Their wealth of experience together shows from Samantha's reactions; Cara must be hitting all of her sensitive spots. You move to get a better view as Sam pulls her face away from Cara's. In her eyes you see the same hungry look Cara had in the doorway, meaning she's now under the craving too.

Samantha lowers her face to Cara's nipple and to your surprise immediately bites it. A shudder runs through Cara, her hands dropping to Samantha's nethers. One hand focuses on her pussy, her thumb rubbing her clit rapidly. Samantha's own juices are flowing freely, giving Cara an easy job. However, the lube on her butt is mostly gone, either from your use of it or simply time. Helpfully, you reach into Sam's bag to pull out her own bottle of the stuff. You squeeze a generous helping into your hand and rub it over her hole. Cara instantly takes over, lubing up her hand sliding three fingers straight into Sam's backside. She moves them in and out, rotating and occasionally separating her fingers to stretch her more.

You move round, squeezing yet more lube into your hand. When you are in position you spread the stuff onto Cara's ass. Samantha's right hand is feverishly pleasuring Cara's pink folds but her left is alternating between squeezing her breast and pinching her nipple, leaving Cara with one hole left unfilled.

Under the rules, most men can't help when women get the craving, but you are not most men. For as long as the two beauties before you are in this manic state you can do whatever you like to help bring them off as if you were another woman. Moving your head to kiss and suck at Cara's neck, you slide your entire length into her beautiful ass in one stroke.

It's clear she's a masochist. That Samantha immediately went to torment her nipples means that she loves the pain it brings, so you know you can be as rough as you like while you fuck her. In no time at all you're slamming your hips into her back, relishing the feeling of her walls on your entire length as you move in and out. Your appreciation of her neck gets rougher, and soon you're nibbling and pinching with your teeth. Her reaction is to close her eyes tightly, her mouth clenched shut to stop her screams and gasps escaping.

Her ass isn't as tight as Sam's, but you suspect it's because Cara uses hers more often. She clenches down on you with talented movements, and though you've been going for only a couple of minutes it feels like you might be reaching your limit. In your imagination you think about all the times you must have done this with her - a masochist who clearly spends a lot of time playing with her rear hole is someone you would definitely want to use your free use power on, and if she's Samantha's roommate you'd have the opportunity often. How many times have you felt these insides wrap around your cock? How many times have you made her cum from nothing but fucking her hard in her tightest hole, exactly how you are now? Did you do it with Sam watching? Do you sometimes alternate between them? Does the sight of you fucking her roommate sometimes set off her craving, and the situation devolves into this mass of writhing flesh, fingers rubbing wet cunts, skin on skin, until everyone involved is utterly spent?

Both girls speed up their movements, crescendoing before the finish. You can feel Sam's fingers moving around inside Cara through the wall between her rectum and her vagina. Every thrust you make brings both of you closer to blissful release. The tightness is almost unbearable. Samantha's thumb on Cara's button must be sending electric shocks through her body, waves of pleasure cascading down. You accelerate your thrusts and know you're nearly there, you're so close-

Cara finishes first, her mouth opening and a scream escaping her lips. A stream of fluid escapes her already sopping cunt, squirting all over Sam who hasn't let up on her movements. Cara's insides clamp down on you and you are totally unable to move as you were, but it doesn't matter. The moment you felt the change in Cara's movements you came, sticky wads of semen painting her insides. The increase in your sensitivity is almost unbearable, but the feeling of release is the best you've ever had.

Samantha is still going, and Cara's orgasm hasn't yet finished. She is no longer feverishly lavishing attention on Sam now though, too wrapped up in her own experience. You reach over and grasp both of Sam's tits, and then pinch her nipples.

It's enough to tip her over the edge. She babbles incoherently and twists on the bed, lost in the rush of euphoria. No longer is she paying any attention to you or Cara. Every thought in her mind is overwritten with the earth-shaking orgasm she's experiencing.

You pull your slightly softened dick from Cara's asshole, but both girls are still coming down from their orgasms. Your hands are still on Samantha's boobs and you lightly grope and squeeze them while she recovers. It takes more than five minutes, but eventually both girls are aware of their surroundings again. They seem chirpy and awake despite how strongly they just came, and while you sit on their bed with your boxers around your ankles they get ready for their after lunch classes. Almost in a dream state you get dressed, say goodbye to the girls and walk across the hall to your own room. Once inside, you sit down and wonder just what you can do to follow that.