MTL - I, The Grandson of Garp, Scared Luffy Into Tears - Chapter 7

Su Yun was a prodigy, blessed by the gods. However, life is never so easy. Soon after reaching 6th stage in spirit novice realm cultivation, his progress stagnated due to incurring a rare medical condition.

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.

In this school fantasy story set in the distant future, creatures contaminated by pollution have overtaken the land, forcing humanity to live in isolated mobile cities called Regios. One such city named Zuellni is a self-contained school in which freshman Layfon Alseif has just enrolled. Layfon reluctantly joins the 17th Military Arts Platoon led by the third-year student Nina Antalk and embarks on a series of adventures.

Perhaps it is the choice of fate. As a senior otaku, Qian Lingfeng got the “steel shell system”. However, when he swept the world with the system, became a local rich man, made all kinds of beautiful women, opened a harem, and realized the ultimate fantasy of thousands of otaku, he found that things seemed far from simple!
When the end comes, biochemical zombies suddenly come down, fierce beasts are in power, bloodthirsty zerg roam to kill the world, and human lives are comparable to dirt. Where will weak human beings go in this world? Is humanity going to be extinct? Or … can an otaku save the fate of the human race?

- Description from Novelupdates