You drink the black goo

You grab the little jar, pop the top, and gulp it down. In a moment your mouth feels cold. Everything touched by the liquid feels icy. Then things start to crack and heat up. It doesn't hurt, but it feels like you're crumbling from the inside out. You jump up and grasp at your throat. You can see a pale reflection of yourself on the shiny office walls. Dark tendrils under your skin are spreading out from your mouth and consuming your body. Soon they spread to your eyes and ears. You crumple to the floor, unable to see or hear anything.

You feel the seams of your suit rupture around your body. Patting your face and chest, you can't feel anything solid. Just a shifting, shapeless, sponge like mass that gives way at the slightest touch. You turn on your back and lie down, waiting for the feeling to end. Will you even have your own face? Is it affecting your mind? The fact you aren't worried at all makes you wonder if it really has gotten to your brain.

Slowly, slowly your vision returns. It filters in, along with your hearing, like a song drifting towards you from far away. Vespa is standing over you. She is decidedly demonic. Her eyes glow and a dark aura billows behind her. You hadn't been able to sense these things before. You lift yourself back up and inspect yourself. Your centre of gravity has shifted and you almost topple over; you've gained a foot in height, at least. The fleshy face that stares back at you in the bathroom mirror each morning has been replaced by an otherworldly visage wrapped in thick red hide. Do you even have 'skin' anymore? You punch your arm - you don't feel a thing. But when you trace a claw up your arm you shiver at the delightful touch. Your body is tougher than ever before and yet more sensitive at the same time.

Vespa is watching you with keen interest.

"How do you feel, big boy?"

"Good... No. Wonderful! Strong!"

You flex an arm. Every ounce of body fat has given way to taut muscle instead.

"It's a pleasure to be on board, ma'am. One thing though - I forgot to ask, are your benefits as good as you advertised?"

"Oh yes. All our salaries start in the six figures. That's the minimum. There is plenty of room for advancement. We've got an entire hell dimension to draw on for raw resources, after all."

"Fantastic! Now, about that sex in the workplace policy," you grin.