MTL - Is the Wife Married? - Chapter 43

People in the World of Naruto: Drinking Makes You Stronger
 Author: Half a Piece of OrangeYouyu, a man who found himself transported into the Naruto world, awakened a rather unusual system:The more he drinks, the stronger he becomes!• Raikage: “What?! I have the strongest defense—wait, why did Youyu just slice through me while drinking?!”• Hiruzen Sarutobi: “That guy’s a monster. I’ve never seen him train, only drink... yet he still cut me down in an instant.”• Madara Uchiha: “Dancing? Tch. That drunk bastard swayed his way over and chopped me up!”• Obito Uchiha: “Damn it! Even space-time jutsu can’t stop that drunk maniac!”Youyu: “My hobbies? Drinking... and cutting people down.”

The unparalleled Demon King Ye Xuan, who was able to heal the death or the living alike and holder of the medicine Holy Scripture, was betrayed and killed by his fellow Demon Kings. But he reincarnated into the body of Ye Xuan, the prodigal son of the Ye family and vowed to himself that he would return to his peak and take back everything that belonged to him!

- Description from Novelupdates

What is my 1000-year-old monster self to do when I’ve failed my immortal ascension? Time travel — accidentally — and wind up back in my 9-year-old body, needing to re-cultivate, of course. But after that? Get REVENGE! Muahahahaha! But the idiot who killed me — also accidentally — was the main character of the dumb harem Xianxia I transmigrated into. But wait. Wasn’t he only 7 or 8 at this point in time? Well, since I can’t harm a child or the main character without suffering in some way, then I’ll just have to raise him better, faster, stronger, and loyal! Muahahahaha!

An alien race invaded the Earth on June 6, 2128. At the midst of this war, many nations allied with the alien threat and the war nearly wiped out the rebelling humans of the planet. At the edge of mankind's survival, the United Nations Army launched its forces to eliminate the immediate stellar threats that loomed over Earth.

General Seeker Carlean, commander and leader of the mission, risked and gave his life to destroy the immediate stellar threat. The battle was won though Earth lay in ruins. Perhaps mankind will live to see a few years of peace before the alien threat returns to wipe out their existence.

At the immediate aftermath of the stellar battle, the fallen Seeker Carlean awakens and finds himself at aged 17, living the peaceful life he lived 16 years before he died.

So begins a new game in the battle for humanity's survival.