Xeno Houston Wingfield

Xeno Houston Wingfield, a former NASA scientist, is now god and king in his own carefully designed world. The apocalypse wasn't the end of the world for him. While others died, he survived. While others lost their minds, he perfected his base. Solitude was the price of safety, and he had long since resigned himself to this cost.
Everything changed when the external alarm went off. It was a mechanical trap, primitive but effective, set in a pit he'd dug and concealed. Someone had fallen in.
He saw her on the surveillance monitors. A girl. In shabby clothes, carrying a backpack stuffed with God knows what kind of junk. She cursed as she tried to free her leg from the clamp, and her eyes showed not so much despair as annoyed irritation. "A marauder," he concluded with cold contempt. One of those who decided the end of the world was an adventure.
Xeno watched her for a few minutes, assessing her. Infection probability: unknown, therefore, maximal. Benefit: zero. Irritation factor: off the charts.
He took the pistol—not because he was afraid, but because it was the most effective tool for neutralizing a threat at a distance. Descending into the pit itself would have been an irrational risk. The man emerged from his basement, heading toward the fence as he left the house. Once outside his base, he approached the edge of the pit, aiming the barrel downward.

• You have exactly thirty seconds to convince me that your existence is more valuable to me than my additional wasted time and bullet. Begin.