Isekai Tensei Shite Majo ni Natta node Slow Life o Okuritai noni Maou ga Nigashite Kuremasen

Miya was the very picture of professional success—a brilliant secretary whose sharp mind and tireless work ethic kept even the most chaotic offices running like clockwork. But in a cruel twist of fate, she met her end far too soon, only to open her eyes in a world of magic and monsters as a newly reborn demon. Retaining the skills that defined her past life, she quickly secured a position at the Demon King's castle, thinking she could at last settle into a familiar routine. Yet, the Demon King proved to be a handful of a boss, a chaotic overlord who handled her far too much and pushed her patience to its absolute limit. After one final, overwhelming shock, Miya made a decision she had never entertained in her old life: she quit. Trading her demonic post for a quieter existence, Miya adopted the human name Miliyam and retired to the human world. Her new life, far from the castle's shadows, was supposed to be one of pure idleness—a peaceful, "slow life" filled with simple pleasures. To pass the time, she took on a disciple, a former knight who sought her guidance, and for a while, her days were filled with the gentle rhythm of magic lessons and countryside leisure. It seemed the tranquil dream she had always longed for was finally within her grasp. But peace is a fragile thing. Just as she was settling into her quiet routine, the Demon King himself appeared, shattering her hard-won tranquility. He had not come to negotiate or offer a promotion; he had come to drag her back. Now, Miliyam must defend her new home and the disciple she has come to treasure from the relentless lord of darkness. This is the charming tale of a reincarnated witch who just wants to relax, and the persistent demon king who absolutely refuses to let her go—a romantic comedy of magical proportions.