In a town encircled by a colossal wall standing 4,000 meters tall, a perpetual haze of smoke hangs in the air due to the numerous chimneys. The townspeople, oblivious to the sky's appearance, live in a world of perpetual gloom. On Halloween night, a deliveryman's careless mistake leads to the heart he's meant to deliver being lost in the smoke. As he gives up the search, the heart continues to beat, its presence now a mystery within the town's smoky shroud.

Poupelle of Chimney Town
In a town shrouded in perpetual haze, the residents have forgotten the stars, having gone centuries without seeing the celestial expanse.