I've Been Killing Slimes for 300 Years and Maxed Out My Level

After succumbing to fatal overwork in her previous life, a young woman is reincarnated as an immortal witch determined never to repeat the same exhausting mistakes. For three hundred years, she commits herself entirely to a peaceful, leisurely existence. To cover her modest living expenses, she casually hunts low-level slimes on a daily basis, treating it as nothing more than a gentle chore. However, centuries of this effortless routine quietly accumulate massive amounts of experience points, and before she even realizes it, she has inadvertently reached the absolute maximum level of power. Her tranquil lifestyle shatters when rumors of a supremely powerful level ninety-nine witch begin to spread across the land. Suddenly, her quiet home is besieged by curious adventurers seeking glory, formidable dragons looking for a duel, and even a monster girl who affectionately claims her as a mother. Desperate to protect her hard-earned serenity, she pleads with the constant stream of challengers to leave her in peace, insisting her home is no training hall. Despite never embarking on a single true adventure, she now stands as the strongest being in the world, leaving her to wonder if the relaxing life she always wanted can possibly survive her own overwhelming strength.