Synopsis: Tegami Bachi: Letter Bee

Amberground's capital city of Akatsuki is shrouded in perpetual darkness, lacking natural light and relying solely on an artificial sun for illumination. Moving away from the city, the surroundings become increasingly grim and dangerous, particularly around Yuusari and Yodaka where massive armored bug creatures called Gaichuu thrive on human emotions. Despite the perilous circumstances, a select group of mail carriers known as Letter Bees brave the threats to deliver letters throughout Amberground. For twelve-year-old Lag Seeing, Gauche Suede is a hero. Lag had met him five years earlier when Gauche delivered the young boy to his current residence as a message from his absent mother. Determined to follow in Gauche's footsteps, Lag longs to join the Letter Bees and solve the mystery of his mother's disappearance while reuniting with his idol.