Ventilation

Your father looks around the nearly empty lunch room for anyone who could help, spotting John throwing away his empty food containers and preparing to leave. Your father waves him over.

John whistles with admiration at seeing the width of the shaft nearly breaking your jaw and the swelling of your stuffed neck, eventually commenting, "Damn, Kev. How did you manage this one?"

"Uh, don't worry about it... Just help me pull her off okay?"

The two men yank and tug at your head, with John pulling your hair wrapped around his fist like he's trying to win a game of tug of war and your father pushing away at your face with one hand and your lower jaw with the other. You kick and squirm in severe pain from the strain and pressure they put on your head as they pull with all their might.

They collapse with exhaustion, giving you a break to zone out again, barely clinging on to consciousness. They discuss the predicament for a few minutes before John has an idea.

"See, the problem is that your penis is causing a suction cup effect as you pull out, making a stronger vacuum the harder you pull," John theorizes. He grabs your ass and begins pushing a finger into the hole as he continues. "What we need to do is get some air in from the other side to release the vacuum and it should slide right out."

"Are you saying we should gape her asshole to release the pressure?" Your father asks, unsure if that's how physics work; but he isn't really sure how any of this works at this point, especially now that nanomachines are involved, so he's willing to try anything. Besides, if there's anyone who can gape your asshole wide enough to release a vacuum in your stomach, it's John.

John lays his own huge cock between your ass cheeks, slightly annoyed to be getting beaten at a size competition for the first time in his life. You feel him poke at your puckered rear hole and try to shake your head no or put up some sort of complaint, but your head is so thoroughly impaled on your father's cock you can only squirm.

Mercifully, John lubes up your asshole and his own massive dick, likely for his own pleasure and benefit more than yours. He begins pushing the head in and you begin to wonder which of your holes hurts more, but you can't decide.

Your father is delighted to discover that for every inch John sinks into your asshole, he can pull out of your throat roughly the same amount.

By the time John has hilted himself in your rear Kevin has managed to pull out nearly half of his own length, but not quite enough to free himself from the suction. All three of you are disappointed that they are unable to free you, but the disappointment quickly subsides as John begins to pull back, drawing your father back in.

The airtight vacuum seal on your digestive system feels incredible to begin with, as it slides over their thick shafts, but the thrusting now seems to take half the effort, since Kevin pushing in pushes John out and vice versa. They work out a rhythm between the two of them, eventually ending up holding still while pushing and pulling your body between them.

They chat about how great this is and how tight you are, even complementing you for doing a good job, as though you're doing anything, while you wonder if you'll ever be tight anywhere ever again after this is over. You wish you could just pass out already, but the pain keeps you awake.

Both men begin to cum at the same time, flooding your stomach from both ends with two huge loads. Your belly starts becoming visibly distended, swelling like you are pregnant as they unload more and more seed into your over stuffed body. You feel like you're going to pop, but you can't manage to pass out.

"Whew! With that amount of medicine she'll probably be freakin' genius now," John states as they milk the last of their orgasms out with your body.

"Isn't that great, pumpkin?" Your father asks, trying to improve your mood. "You probably got a months worth of doses in a single day!"

John pulls himself out, pulling your father back in until the words 'FUCK TOY' written on the patch once again fill your field of view as your face nearly comes to a rest on on his pelvis. The moment John's cock pops free of your rear you begin to gush cum out of your gaped ass like a fountain.

Your belly shrinks more and more as you eject the pressurized stream on to the break room floor while the two men watch on in amazement. It shoots out for so long that John even manages to pull out his phone and take a picture of your shameful display. He sends it to your father.

Once the fountain finally stops and you no longer look pregnant, your father tries to pull himself out of your throat once again, but to no avail. They both stretch your empty asshole open as much as possible, trying to let in enough air to release the vacuum, but he can only pull back a few inches.

The two men look disappointed as they finally give your gaping ass a rest. Your father is happy to be able to move several inches now, allowing him to comfortably fuck your throat, but the nanobots are still keeping him painfully erect, even after an orgasm.

Kevin thanks John for his help and lets him get back to work as he tries to figure out how to dislodge his daughter from his cock.