Victory is at hand as the latex continues its retreat, soon running out of space to retreat to. You've covered your leg up to the knee in oil, and now it can barely move any further. Then, it does something unexpected: it starts moving back down. In one last, glorious act of defiance, all of the rubber that had collected at the top of your leg starts pouring back down, dissolving instantly as it hits the oil. Even despite this, it keeps pushing downwards, and eventually it starts to gain some ground. Just an inch or two at first, but before long it's down past your knee again, and then down to the bottom of your shin, and then right down to your ankle. With your foot still fully submerged in the oil, that should be the end of it... but it's not. It expands around your ankle, gathering into a pile, and then explodes downwards. The push is slow, but even from the angle you're watching you can see what's happening: it's cutting through the oil. Bit by bit, it's pushing right through, and the dissolution is happening less and less. You hold your leg firm, doing the only thing you can to fight back, but it's useless. The latex finishes pushing downwards, enveloping your leg in the same featureless, strangely shaped lump of latex flesh as before.
"NO!"
You stomp your foot in the puddle a few times, the oil splashing right up your leg, but it does nothing. The latex remains, now completely unaffected by your efforts.
"This sucks," Steve offers, clearly trying to make you feel better about the loss of your leg. "This really sucks." He jams his own, far less affected hands into the oil, and his latex vanishes near-instantly, leaving him completely free of infection. "Look, there's got to be something else we can do. We'll just have to think of it."
"Yeah..."
You look over your changed leg. It looks the same as it did before you even touched the oil, but somehow your perspective makes it feel different. Knowing that it's a permanent fixture on your body just makes it look so much scarier.