Say nothing

You wince as the firearm discharges over and over again, the slugs piercing into the train-sized centipedes soft innards. An angry hissing fills the air and the tendrils tighten, brutally crushing the air from your lungs. You can't breath, you don't have the room, and you see the captain quivering next to you in a similar predicament. Seconds tick by and you dimly see her grip on the pistol slacken, the firearm dropping from her hand and clinking away down the side of the siege-breaker as it changes course, moving upwards.

You're barely conscious as the three of you emerge from the tunnel into what looked to be an old gymnasium. Golgothi roots cover most of the room including the windows, letting in only dim light. The beast rolls over, flipping you two wildly around in the air, and two of its chitinous plates of armor sprang open like the trunk of a car. You are unceremoniously dropped into the upper compartment, dimly aware of the Captain being lowered into the other. You land on something wet, soft but firm, and you take a long, rattling breath as slimy appendages slither over you. Just as you manage to get your bearings, seeing that the creatures tentacled innards had you suspended by your arms and legs, the creature's armor seals itself and you are trapped in blackness.

You feel dozens of wet muscles sliding over you, like impossibly long tongues, slipping under your clothes and slathering every inch of you in foul-smelling ooze. Your clothes come apart easily, as though they just dissolved, and you shudder as the creature's tendrils locate your sensitive points. Your cock rises to full mast, batted around by the slimy tendrils almost painfully, but that didn't seem to be their goal. You squirm and shriek as one slides over your perineum and between your asscheeks, gasping in relief as the **** suddenly stops and you are left alone in the dark space for a moment as the tendrils seem to reorient themselves.

Then you feel it: a particularly thick tendril prodding directly at your virgin rosebud.

"Wait, nonononNOOO!" It surges upwards, pushing into your tightest hole with brutal **** somewhat alleviated by how slimy the tentacle was. It slows as soon as its inside, swirling and twirling like a particularly well-muscled tongue. The end seemed to have a larger bulge as you feel your sphincter tighten again as it pushed onwards, groaning involuntarily as it stimulated your prostate, half-hard cock surging back to full mast.

It seems satisfied with your insides, pushing further inwards... and further... and further! You scream out, not so much in pain as in principle: nothing should be this deep inside you. And it doesn't stop, sliding deeper and deeper, you feel your sphincter start to stretch again as the tentacle's natural girth spreads you out. You feel it turn bends and wiggle through barriers, filling you in a way you never imagined, all the while oozing copious, musky slime.

You squeal and cry for it to stop even though there is no pain, quite the opposite in fact: the constant sliding against your prostate is pushing you towards one of the fastest climaxes of your life. It suddenly pushes through into an open space you realize with some shock to be your stomach, surging forward and coiling around till you feel as though you ate a much too-large (not to mention, alive) meal of calamari. You can't take any more and your girlcock erupts in a hands-free orgasm, the pitiful quantity of slightly warmer semen quickly lost in the ocean of slippery tentacles.

You retch reflexively as it pushes up into your esophagus, coughing as it tickles the back of your throat, and with a final groaning protest, you feel it slip past your lips and slap across your face. Finding only empty air, it retracts back into your mouth, seeming to enjoy wrestling your helpless tongue around.

(Credit to Piratepup for art. Mentally add girlcock if you so desire.)

Time stretches on for a bit, you feel your cock erupt in several more prostate-fueled climaxes from the stimulation of the thick base of the tentacle in your ass. The tip was restless in your throat, barely letting you get a full breath of air as it pulls this way and that on your tongue. It even wiggles up into your nasal cavity at one point, squishing into the tight space and spurting a load of slimy lubricant out your nose, before finally seeming to get bored and retracting. You feel downright empty as the stupidly long tendril sucks back through your guts like fluid in a party straw.

You moan in what you don't even pretend is relief, your cock threatening another tired orgasm as the tendril pops free of your stretched rosebud. Maybe it'll just let me go now? Let me sleep? No such luck. It is with dawning horror that you feel another thick tendril slide into your ass a ways and stop... thick bulges moving along its length and depositing hard round things inside you.

You laugh, slightly deranged, from the circumstances, "Hehehe... guess the intel was wrong, huh Captain...?" you cum again as the siege-breaker pumps its eggs into your asshole, your well-stretched hole to be the nursery for its one day titanic young.

The burn zone is overrun in the next months by a wave of siege-breakers, the huge aliens bursting through the reinforced walls and wreaking havoc.

Far above, resting in the bathtub-shaped container you considered a bed, you burble in annoyance.

"GUESS I'LL HAVE TO DO SOMETHING ABOUT THE GOLGOTHI... UGH..." You flick to another channel of your drone observations while you debate whether to boost the human defenders or weaken the alien swarm.