MTL - The Male Lead’s Substitute Wife - Chapter 21

Kusumi Chiharu gets a message one day that he has been selected as a Monster Tamer, and he is prompted to select his first partner. He thinks little of the message until he receives a giant package the following day. He assumes it’s the porn books he ordered, but the huge box ends up containing the unconscious body of a near-naked girl! She’s a ghoul named Zonmi, who intends to fight beside him as his partner.

However, it turns out that other hot girls at his mostly-male high school are also magical entities, and Zonmi may not be the only one who wants to fight by his side!

I fell into a game world out of nowhere with an instant kill skill.
And then somehow, I became a bigshot.

Medieval times, warring knights, dragons, demons, gods, pirates, behemoths...Barbaric, ignorant, backward, numb, starvation widespread, people unable to make a living...Damn it! Punch to explode this era!!Reclaiming wilderness, farming, bridge building, road paving, coal mining, excavating minerals!Leveling up, recruiting apostles, forging an army!Barrage troops! Pushing horizontally!Quack! My steel torrent is invincible in this world!!Roman: “I am your destiny! Kneel before me!”So, you were supposed to farm, but somehow you ended up establishing a vast empire and becoming the emperor?

Have you ever thought that the state of the world as it presently is, could revert to the laws of the ancients? When a series of strange incidents beginning with the disappearance of his friend led Luo Yuan to question the possibility of an apocalypse, he becomes embroiled in the midst of a global-scale chaos.

Evolution has turned the flora and fauna of the vast and bountiful Earth into something that had never been seen before. Coincidentally, the all-dominating Homo sapiens have ended up at the bottom of the food chain. From mystery to crisis, will Luo Yuan discover a means of saving humanity by racing to the top of the food chain? Or will he strive in accordance with the law of the jungle? It is the dawn of an age of the survival of the fittest.

- Description from Novelupdates