"... you can cum in my ass."

Peter's eyes spark with a hungry glint. You realize, quite miserably, that you've offered him exactly what he wanted. Already resigned to your fate, you prepare to step into his room so he can have your ass.

He surprises you by holding up a hand to stop you, while conveniently grabbing a palmful of tit flesh. "One more thing," he says. You really don't like the look on his face. The moment draws out, and you shudder when he starts kneading and molding your breast.

"What!? What's the one more thing?" you finally shout.

He answers quickly, "All you gotta do is keep my load inside you all day at school. That way it gets nice and marinated up your asshole. Then you can shit it out tonight and I'll watch you gobble it up."

You stare at him in horror. It's not unusual for your brother's kinks and desires to throw you for a loop, but this crosses a line. This crosses several lines. Not only is it disgusting, but it goes far beyond any medicinal justification. Your mouth flaps a few times as you try to formulate the right words.

But he shrugs after a few seconds of silence, and moves to close the door. "Alright, I guess you'd rather I just feed all my cum to Mom instead. I hope Dad is up to being your only regular-"

"You're a fucking ass, you know that?" you interject. Cutting him off like he did to you feels good, but it's significantly tempered by what you're about to say next. "Fine. I'll do it. I need the dose, okay? I'll do it."

By now, you're practically in tears. It just isn't fair! Peter knows it, and he revels in it. With his widest, shit-eating-est grin yet, he pulls you into his room and shuts the door behind you.

Your brother wastes no time. Mom and Dad will be wondering what's taking the two of you so long to get ready, so you appreciate his haste, if not his roughness. You're manhandled onto your knees and then bent over Peter's bed in a matter of seconds, and before you can react, his dickhead is pressing against your sphincter.

"Wait!" you gasp desperately. "I need a minute to- Oh, fuck!" Just like that, he's inside your ass. Peter doesn't believe in foreplay, or really anything that could make donations more pleasurable or comfortable for you. Of course, as a medical procedure, it's not technically meant to be pleasurable, but his bedside manner still leaves a lot to be desired.

You bite the sheets as he thrusts. It's dry and it's tight; despite how often you've had it up the butt, you're young enough that it (mostly) tightens back up soon after. That's a good thing for your donors, not so much for you. Peter obviously doesn't care that you're in agony. In fact, the tighter you clench in pain, the harder he hammers into you. Your muffled squeals and groans grow louder and more high-pitched, as the sound of flesh slapping flesh fills the room.

Peter grunts down at you between thrusts, "Yeah, take it, you, bitch! Take, my fuckin', cock! Take, my, load! Gonna, shit it, out! You, fucking, whore!"

He punctuates that last word by embedding himself in you balls-deep, which is where he stays buried as his hot spunk blasts into your bowels. Spurt after spurt unleash into you, and all you can think is how you're going to have to squeeze it out and eat it tonight. You are suddenly filled with regret - almost as much as your rectum is filled with sperm.

Before long, he rolls off you with a grunt. You're left flattened against his bed, ass up, the lower half of your body tumbled loosely on the floor. You can feel your anus winking in the cool air, but inside feels like it's on fire. Peter's load sticks to your rectal walls. It slowly oozes deeper into your body, helped by gravity. You're overcome with the need to stand so that it doesn't go too deep inside.

But Peter is quicker. You sense him standing behind you, and a moment later, something cold and firm slips into your sore asshole. A yelp escapes your lips, and you immediately jolt backwards off the bed. Peter, displaying much more agility than you'd have expected from your layabout brother, pulls the device between your legs and inserts a second bulb into your pussy. As you frantically tug on the plastic now plugging both your holes, Peter latches the belt around your waist. The click of a lock confirms your fears.

A few fruitless seconds are spent trying to remove it, but you know there's no point. Smoldering with rage, you cast a disbelieving glare at your laughing brother. He sees the look on your face and laughs even harder.

"Peter! What the fuck!" you bark. "You put me in a fucking chastity plug? A double chastity plug?!"

You learned about chastity plugs in school, from the new Life Sciences curriculum for girls. Well, technically speaking, you only learned about regular chastity belts in school. Due to the importance of penis-in-mouth sex acts nowadays, some women have taken to forcibly restricting the ability for men to waste their donations in other orifices. A growing portion of the female population is opting to wear chastity belts while out and about. There's a whole social movement behind wearing them, which likens chastity belts to panties or brassieres in how commonplace and comfortable they should be. However, most people consider wearing one regularly to be borderline suicidal due to the commonly held belief that they result in much fewer donations. No one really knows for sure if that's true, though the practice's proponents claim it actually increases the proportion of medicine that a patient ingests.

All of that is beside the point. A chastity plug is not built for medical reasons like its belt counterpart. A chastity plug is a fetish accessory, and a double plug - which is inserted into pussy and ass as opposed to one or the other - especially so. The idea is similar to how chastity belts in the pre-disease era were seen, or so you've heard. If people could find it thrilling and erotic to deny themselves orgasm under lock and key, then others could find it even more intense to deny themselves a lifesaving sexual fluid. Some can even vibrate, though you don't think this is one of those. Funnily enough, chastity plug wearers and chastity belt wearers are both restricting access to their bodies, but for opposite reasons - belters think it gets them more doses, while pluggers think it gives them less. The debate rages on, but all you can think about is how you want to **** your brother right now.

"Hey, I had to make sure you kept my load in there somehow, didn't I? Sorry it's a double," Peter says, shrugging. "I wanted a single anal, but this was all I could find. And don't worry, the key is hidden somewhere safe. You'll get it after school." It sounds like he's been planning this for some time. You fume just a little bit more, making short, choppy sounds like you want to yell at him but you're too apoplectic to form coherent words.

"What the hell are you still doing in here, Sarah?" he asks, with the gall to sound annoyed at you. "We have school soon. Better wear a longer skirt than usual if you don't want people to think you're a prude."

Peter's right. If you're caught wearing a chastity belt, let alone a plug, word will quickly spread through school. You might never get a donation from your classmates again. And the fact that it's a plug could be taken to mean you want to be sexually abused in an actually sexual way - not to extract doses. It's a terrifying thought.

Needless to say, if your parents found out he plugged you, they would rip him apart. Then again, they might rip you apart too, for even allowing it to happen. Somehow, even when Peter is in the wrong, it always seems to come back and get you in trouble too.

You could rat Peter out to your parents, or you could risk a day plugged in chastity. Neither sounds particularly appealing. You storm out of his room, slamming the door in the process, and escape into your own room before anyone else in the family sees you. Tears brim in your eyes. What the hell are you going to do?