The Simple Life of Killing Demons - Chapter 17Book 12:

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.

In the past, the giants of the heavens and the gods were destroyed after the reincarnation of the world! Cruel curse, eternal hatred, Tan Yun is determined to never sink again! For the sake of loved ones and relatives, from now on, step on the corpse of the enemy step by step to surpass the peak! Defying the sky, killing all worlds, I am the only one!

- Description from novelbuddy

Edwin was once a world renowned scientist, attested for his understanding in genetic. Was. Involved in a scandal, he was disgraced and thrown to the dirt. And when he wanted to commit his final act of revenge upon the one who threw him there, he die, not by the assassin sent after him, but death through the illness that have been plaguing him since childhood.However, after death, he soon woke up in a brand new world, one filled with magic and monsters. However, he woke up as demon, enemy of humanity, and given a system that will help him empowered monsters through either magic or genetic modification.-x-“Hah, enemy of humanity, I like that. When have human ever been grateful to me! Now, I will plunge the world into an age of demon and monsters!”Filled with desire to watch the world fall into ruin, Edwin, now Alros Kadarni, will cause as much destruction as he can. From one kingdom to the next. From one continent to the other. All by using the different danger zones that is feared by all sentient beings that is not monsters not demon.

In an inaccessible village, there were a few houses on the hillside.

People from far away were attracted here and the mountain road was crowded with luxury cars, because, in this town, there was a young man with incredible medical skills who could cure all kinds of illnesses!