There's a lot of pressure on you when you're the man who counts. One slipup, one distraction, and all of eternity is off. Even if by an infinitesimal amount of time, the universe is changed forever.
The man who counts knew of these dangers. So he locked himself away, in a small village on an island in the ocean, where the lulling waves helped eased his consciousness into rest. But his brain kept working, day and night, never daring to stop.
Years passed, and he never even heard the loud grinding of parallel white lines being cut into the side of the hill on which his cabin resided. The lines were a warning, for an entire generation withered away, and the descendants took off in ships, never to return again, likely dying at sea of whatever disease they carried. He distinctly remembered a weak pounding at his door one day. But the count could not be interrupted, so he did not rise to answer it.
The island must've been discovered, eventually. Corpses were strewn across the beach, and buildings decayed to the ground… except for one. His home was in pristine condition, like it had just been built. The explorer knocked, but again, the man did not answer. Even through the door being kicked down, he sat perfectly still until the slightest breeze bristled his skin, at which he jumped to his feet, jabbed his arm forward, and voided the explorer's heart.
There was no time to waste. His home was already falling. So he left by boat, counting day and night as he tended to the sails. He'd spent eternities coasting on the ocean, so muscle memory was able to take over quite fast. The man didn't think of what he left behind— it was but a sojourn, a brief resting point. It was time for someplace new.
He did not ponder, for even a moment, where he was to go. To wander would be the answer, until he found someplace calm. Months later, he found that place.
Going up the mountain was a dangerous trek. Multiple graves littered the trail, little crosses painted onto the basalt everywhere he looked. He was tempted, for a moment, to count them. But it wasn't important enough, so he continued his climb.
Finally, he reached the top. Still, it was not time to rest.
He looked into the crater at the peak, watching as the magma boiled in the hole below it. This volcano was not set to erupt for millennia.
So he took a step forward, plunging into the scalding abyss, and the count continued once more.