An idea proposed by

Text from message I recieved:

"...It would be that rubber gasmasked...thingy, and another girl "victim". Her specifics would be totally up to you.
What you'd have is that rubber alien thingy holding her from behind with one arm wrapped around her midsection, while the other would be holding a gasmask to her face that looks exactly like the one it has on, but mostly just the forward area for now. You can see her eyes through the holes still, looking a bit...distressed. The black rubber would be spreading around the girl's body from the points of contact (arm, back to chest, mask edges, etc...), like a creeping rubbery liquid slowly covering her over. You'd still see areas of her naked body showing here and there that haven't been covered yet...but at least 60% of her should be covered in shiny blackness.

Basically, the overall premise is that it snuck up behind her...maybe in her bedroom or somesuch after it snuck in, looking to assimilate someone. It's a very sleek, sensual creature, so it wouldn't be rough with her...it would simply sneak up from behind, and snatch her up against itself. As it was creeping up, the tube would extend down from it's own mask, and some liquid rubber would form into a basic gasmask shape, with rather wet edges. Just as it snatched her up, it would slip that attached gasmask up with it's free hand and press it to her face, immediately silencing any cries for help she might make. Then slowly the areas in contact with her body would go semi-liquid, and start to creep black rubber all over her body. As it did, it would give her it's exhaled breath, which is naturally laced with mental sedation to help make the person complacent and welcoming to the change.
By the end of it, she would be covered all over, and look like a copy of the other alien thingy. The hose would detach, the lenses in the hood would go black, and she'd be fully under the control of their little mental collective..."

And the refs I used from 's gallery for the thing:
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