Hidden Dead Ends - Chapter 61

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

Nanaya traveled to the Naruto world and survived the Uchiha genocide incident.As long as he sleeps, he can become stronger and invincible.After accumulating 60,000 hours of sleep, Nanaya opened the Sharingan and activated the ability of the Ice Fruit.Itachi: I didn't find his existence on the night of the extermination. Who is it?Sasuke: Nanaya, my Amaterasu's black flames can burn all visible objects, otherwise they won't go out.Next second!“What, Nanaya, you guy, actually froze my black flames.”Pain: That guy just slept for a second in the gap between Shinra Tensei, and the power to wake up is above me.Madara: I can't dance in front of that man.Kaguya Otsutsuki: My world of ice can't even live up to that sentence, ahhhhh!Uchiha Nanaya, with a pair of Mangekyo Sharingan, changes the past and reverses the future.

But things seem to be different from the history that he knows.In this strange land, ancient legends walk the earth. Here Witches, Manticores, Vampires, Werewolves, Sirens, Dragons and Krakens are all terrifyingly real.As if that weren’t enough, this is also the age of legendary rulers—Baldwin, Saladin, and Richard the Lionheart —each destined to shape history in a new wave of Crusades.Amidst bloodshed and glory, Lothar must use his only advantage—his Gacha System—to build his territory, summon legendary units, and carve out his legacy in a world where ambition reigns and power speaks.

My childhood friend went to the academy.