"I Was a Bottom-Tier Bureaucrat for 1,500 Years" is a manga series that blends fantasy, comedy, and slice-of-life elements. The protagonist, Azusa, is an immortal elf who has spent 1,500 years working as a low-level bureaucrat in a fantasy world. After centuries of monotonous paperwork and minimal recognition, she decides to retire and live a quiet, peaceful life in the countryside. However, her plans for solitude are quickly disrupted by a series of unexpected events and encounters with eccentric characters.

Azusa's life takes a turn when she inadvertently becomes a mentor to a young dragon girl, Laika, who seeks her guidance. This marks the beginning of Azusa's gradual involvement with a diverse group of individuals, including a reincarnated former colleague, Falfa, and her sister Shalsha, who are both plant spirits. The narrative explores Azusa's interactions with these characters as they form an unconventional family unit, navigating everyday challenges and humorous situations.

The story also delves into Azusa's past, revealing her long history as a bureaucrat and the relationships she formed during her tenure. Despite her desire for a simple life, Azusa's unique abilities and wisdom often draw her into resolving conflicts or assisting others, showcasing her growth from a detached bureaucrat to a compassionate figure. The series balances lighthearted moments with occasional reflections on immortality, responsibility, and the value of human connections, all set within a whimsical fantasy world.