The Strongest Interstellar Commander - Chapter 3: Tactics.

In a romance novel called “The Secret Lovers of the Academy” the male lead would often torment his fiancée–but wait, why did she cross into this world to become his fiancée, the villainess, instead of the heroine?

Louise Sweeney found the perfect solution to escape the misfortune of being the villainess: “Your Highness, I just want to tell you that we don’t have to be tied with our engagement. We weren’t even officially engaged, right?”

But what was wrong with the male lead’s reaction? To her suggestion, he replied “But our engagement wasn’t false, don’t you agree?”

Transmigrating into a poor and mistreated young lady's body, what will the craziest alchemist of the seven realms now do?

The dawn era after the end of the half century has gradually rebuilt the order, abandoned civilization, and is full of undivided violence and desire.
The noble and powerful pioneers are in charge of the city, and the evil and mad plagues are in the wilderness.
Pure human beings who cannot mutate are the weakest, dominated by the rulers of the pioneers, and are not as good as animals in the wilderness.
A purely humanized young man with a worldly experience has quietly entered the WTO, holding a three-foot long knife and a long-distance desire to boil in the world of purgatory. From the nameless name to the sorrow of the Supreme Court, the name of the black ride is resounding!

- Description from Uukanshu (translated)