Rebirth of 1985's Best Doctor - Chapter 71 - Swap

This is a game that surpasses dimensions.

Our straight (?) bottom woke up ten years into the future and found himself on the bed of his childhood friend… At the start, the bottom was shocked to his very bones, but he soon quickly accepted this premise and found the whole situation to be rather amusing. Precisely then, the bottom once again went back to his timeline — back to when he and the top were just platonic childhood friends.

The simulation is over, and the entry is obtained: a showdown!

Looking at this entry, Zhao Meng was stunned.

“How should this term be used?”

“Hey! Here’s a wounded fox!”

…

A few years later, a woman who looked like a fairy appeared in front of him, and said:

“My lord, I’m here to repay my favor!”

This book is also called “Starting from Transforming Monsters”

- Description from novelbuddy

The one single goal in life of the Strongest Old Sage is to subjugate the Demon King. In an epic final battle, both of them met their mutual destruction at each other’s hands.

However, the Demon King was not completely destroyed!

In order to destroy the Demon King once and for all; post-death, the Old Sage trains in the World of Gods and reincarnates as the Apostle of the Gods, Will.

In the reincarnated future, the Old Sage had become a legend and his former disciples hold the supreme authority in the world. The disciples had created an organization to oppose the Demon King and an academy to nurture the new generation of Heroes.

Thus the Apostle of the Gods, Will (8 year old), enrols into that Academy of Heroes.

This is the story of a boy on a mission to save the world through epic battles while enjoying Academy life.