Akuyaku Reijou wa Danna-sama wo Yasesasetai - Chapter 133 - extra 7

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

- Description from Novelupdates

Baek Yigang is a son of the Baek Clan, one of the seven great clans of Zhongyuan. Afflicted with the Taiyin Qi Blockage, he is cursed with a shortened lifespan and the inability to collect internal energy. He had been peacefully spending the rest of his days indoors when he was ambushed by a group of masked people. During the ambush, he lost his servant who was like a sister to him. Chased by the attackers, Baek Yigang escaped through a secret underground path. When he came across a blocked path, he decided he’d at least die fighting and picked up a rusted sword that was stuck in the ground…

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.