I Leveled up from Being a Parasite, But I May Have Grown Too Much - Chapter 81 - Looking for the Tsujigiri

The Republic of San Magnolia.

What will happen if your ordinary life becomes not so ordinary? What will happen if your old existence becomes anew? What will happen if the world that you know is changing?

Our heroine, Anne, is a 40 year old librarian, that got entangled in mythical magic, inside a mysterious fairytale book. When the disaster happened, she got thrown into another world, the kingdom of Valorian, where magic and lore are coming alive. A world where she becomes younger again, but with a wisdom and knowledge of a forty-year-old woman.

I, Zatiel, Abyssal Lord, Ruler of Death and Destruction, Nightmare of Dys, have AWOKEN!!!!!.

His life contains events that can shake the universe:
-Fighting against Tiamat, Creator of Evil Dragonkind, in the first circle of hell, while billions of demons and devils butcher each other beneath them
-Start a World War against the Heavenly Race, and transform himself into a Golden Sun while he slaughters their greatest warriors, the Archangel.
-Enter the Final Gate and fight against the Outer Gods.
-Tearing the nine levels of Baator during his battles against the Prince of Evil, Asmodeus.

With his memories as a ruler of the Abyss and a Universal Existence, Zatiel will rise again.

When an era came to an end, various forces set foot in cultivation to compete for immortality. A young boy who spent most of the time sleeping got lucky in the troubled times and became an unparalleled immortal who could cover the sky with a snap of fingers. Was he going to live forever?

- Description from Novelupdates