Supreme Casanova: Ultimate Harem System - Chapter 17: The Bet.

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates

The story is about a boy entering high school, who answers a strange call from a public phone one night. The caller challenges him to a bet: She’ll remove the birthmark which he sees as the cause of so many problems, and he’ll have fifty days to win the heart of a girl he’d considered far beyond his reach. And with this, a very strange summer begins.

The world was never the same after that day.Humanity learned that they weren't alone in the universe, but that wasn't something they had the time to worry about.Their realization was accompanied by catastrophe.Creatures beyond their wildest imaginations poured down from the sky and appeared from the earth. They slaughtered humans as if it was their singular purpose, driving them to the brink of extinction.The people of the world did everything in their power, developing unique traits and technologies to create a united front their enemies couldn't penetrate.They secured victories and repopulated, feeling as if they stood a chance against the foreign invaders.They fought and they fought, doing everything they possibly could to ensure their survival.Until the Great Calamities appeared.In front of them, humanity was nothing regardless of its efforts.One by one, the worlds were turned into piles of rubble in between the cracks of their teeth. Civilization was torn apart, and the evolved humans living within could do nothing to stop its collapse.Humanity itself was left extinct, and in the end, only a single man was left alive amidst the chaos.Why?For what reason were they punished so?Nobody knew why the attacks began in the first place.He looked into the distance at the memories of the past and firmed his resolve.“It can only be me.”He knew of a miracle that could return him to the place of those memories.He knew of a way to make the wheels of time spin in reverse.And using it, he alone would save humanity from its doomed fate.That was his sacred duty as its final survivor.

What if life could be repeated?

But he became the clan uncle who was once called a lunatic?

Alas, wearing open-crotch pants in front of me, crawling on the ground, is it my two-year-old self?

I originally wanted to give my former self more New Year’s money, but I never thought that I would go from a braised pork stall to a food giant, from a small factory to an industrial empire.

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