It was late at night. I was hard at work in my lab when I heard his voice.

“So you found a loophole.”

I never even broke my gaze away from my work. I knew it was him and I knew what he wanted. “So I did. Lucky break, I guess.”

“Is that how you see it? Because I see it as stacking the deck.” He spun me around to face him. His eyes were cold, not quite furious but not quite calm, either. “Had I known you would use the funding for this, I-“

“Would have never made the deal in the first place, blah, blah, blah,” I mocked back, cutting him off. I had outmaneuvered the Devil himself. Why not enjoy it? “Now if you’ll excuse me, I have to finish this latest batch to show to the buyers tomorrow.”

“Yes, from a major pharmaceutical company. I’m taking the formula public. I’ll be rich and I’ll be immortal. And who says you can’t have it all?” I turned back to my work but stopped when I heard a slow clap building behind me followed by…laughter?

“That’s all I wanted to hear,” he chuckled. “Job well done.”

“With that formula public, immortality will become widespread and rampant. It will be fun at first, nobody dying, but eventually it will get boring. Add in the fact that no deaths means overpopulation will rise exponentially, draining the world’s resources faster than ever, and soon people will be begging for a death that will never come.” He leaned closer as he softly said, almost in a whisper, “It will literally be Hell on Earth.”

I stood there, stunned, as the weight of his words hit home. He was right. How could I not have seen it?

“The best part of all,” he added, as he took my latest sample and strode towards the door, “is you get to hold up your end of the bargain, after all. An eternity in Hell, paid on schedule. Think about that when you accept your Nobel, Doctor.”

Source: first top-level non-bot comment from r/WritingPrompts.