Something on the other side.

You can feel your ass has gained some more... jiggling to it, and consider going back to try another approach to the problem, but you hear something on the other side of the wall.

You dont have enough time to return so you decide to push with all your strength, but even though you move a few inches, you only manage to make yourself even more stuck. Your struggles get the attention of the creature behind you and you hear it running towards your location. Whatever it is, this creature seems to be small, have many legs and... wet. Your observation is quickly explained as the creature hugs your legs with its many tentacles, speading some kind of sticky substance all over your bottom. You try kicking, but you can't do much beyond shaking your ass and the creature with it, causing the substance to quickly cover your entire legs.

The creature crawls up towards your larger-than-normal butt and pushes your robe away, revealing your bare crotch to whoever looks in your direction. The creature seems to be surprised when it seems your "chastity belt", but it quickly adapts and improvises. You feel of its tentacles touching your clit, the only exposed part of your pussy, and it sends a shiver up your body. The creature rubs your button around, making it wet with the substance, but quickly gets bored and climbs your ass.

That's when you feel an odd sensation on your legs. The spots where the creature touched you before begin tingling, then stinging, then burning. It's like your skin is being sanded, and it hurts. You try concentrating through the pain, but it's too strong. The substance must be some kind of acid, and it's burning your skin out. You feel the pain climbing up to your crotch, until it reaches the spot where the creature last touched: your clit. The sensitive flesh begins stinging just like your legs did before, an almost unbearable pain that you can't do nothing but take. But, due to the region it's affecting, the pain somehow makes you horny. You can feel your skin becoming thinner and weaker, but at the same time it becomes even more sensitive and erogenous, making your legs twitch not only in pain, but in pleasure as well.

Your focus on the pain is divided when you feel the creature moving again, and spreading even more of its juice over you, this time on your ass and, not long after that, your anus. The creature leaks the substance all over your bottom, with a tentacle spreading it. Oddly enough the creature seems to be completely ignoring your virgin pussy, something, you assume, is due to your mysterious chastity belt.

With the large, lubricated tentacle it used to spread the substance, the creature forces its tip into your ass, spreading you for the second time tonight. It doesn't waste any time before thrusting almost 12 inches deep into you, twisting the wet member around, drawing unwanted gasps from you. It keeps thrusting just as deep as the first, but after a few seconds on this, the acid in and on your ass begins burning. Just like before, it hurts and pleases you, but the combination of these alien sensations and the rough fucking you're receiving **** the approach of your orgasm.