The otaku died of a terminal illness and took over the body of Kokushibo from the Demon Slayer world.

In order to survive and make up for some of the regrets he had when watching the anime, he decided to become Kokushibo and live in this world...

Evil spirit + joins Muzan + eats people + no system.

(The protagonist is very bad! Very bad! No humanity, please don't mind if you accidentally enter!)

Manami, who depended on his younger brother for survival, joined the Demon Slayer Corps and became the disciple of Yoriichi Tsugukuni, the most powerful member of the Demon Slayer Corps. However, he failed to kill Muzan during an encounter with him, and thus became a sinner of the Demon Slayer Corps. He was expelled from the Demon Slayer Corps along with his master Yoriichi Tsugukuni.

When he met Muzan again, he had two choices: become a demon and make those who hurt him pay the price, or continue to live like garbage.

Wan Mi chose the former.

Since you have expelled me, I will live my life in the most horrible way possible!

If the Demon Slayer Corps can't tolerate me, then I will become an evil demon!

In the virtual world of "Tianyu" (Sky Domain), telling the story of a butterfly larva growing into the ruler of the insect race. A former level 420 knight dies and is reborn as a blue-eyed butterfly larva in the game world, beginning an adventure of continuous evolution and growth to become the master of all insects.

( Golden Finger + No Female Lead + Decisive Killing)

The world has changed drastically, and spiritual energy has revived.

Animals, plants, and insects have begun to mutate when spiritual energy has revived, but humans have not changed at all.

Artillery fire cannot heat the skin of mountain giants, missiles cannot blow up insect nests deep underground, and nuclear weapons cannot eliminate giant beasts in the sea.

Evolution, cultivation, and becoming a beastmaster are the mainstream and everything in this world.