My Classmate is 200 Million Years Old - Chapter 9

After dying prematurely from an incurable disease, Yuka Hikano finds himself in a mysterious realm filled with endless doors, each concealing divine gifts from powerful deities. He is not alone—others who have met the same fate of death stand beside him, unaware of the trials that await.They are put through various tests and eventually transmigrated into different worlds. But these worlds are nothing like the Earth they once knew.For Yuka, however, this apocalyptic world feels eerily familiar. It is a realm of endless war, devastation, and chaos—a world he once played in a game. Certainly not the kind of place one would wish to be reborn into.From infancy to adulthood, he must gather strength, knowledge, and allies to survive the horrors that lurk ahead. But when he awakens a system granting him a power beyond imagination, he soon realizes that blessings can also be curses.[You have gained Infinite Mana.]Infinite Mana...?What could possibly go wrong?

Traveling through different worlds – this is unscientific!

Get cheats – it’s science!

…

This is a simple story. An ordinary person lives in a different world, farming and raising flowers, studying unscientific science in his free time.

until the end.

- Description from novelbuddy

A world where waves of monsters descend every night...A world where only the strong can survive.Axel, a burned-out man from modern Earth, wakes up in a desolate wasteland with nothing but a strange “Harem Settlement System” with him.Given the power to build, command, and grow stronger, he sets off to carve out a safe haven in this broken world. But as his settlement grows, so does the number of beautiful and deadly women drawn under his blanket-ahem!-banner.Witness Axel's journey, rising to to the peak. From a simple, lone survivor to becoming the Wasteland Overlord. With the help of the loyal, dangerous, and irresistible thirsty harem girls!