Magika no Kenshi to Shoukan Maou - 5.1.1 — Strength, the Time It Should be Shown

The empire had called him a villain, now they raise him as their heir.Once feared as the most powerful being alive, the so-called “Villain of Chaos” was brought down by the very heroes who craved his artifact. Now, he’s been reborn into the very home that had killed him in the name of cleansing the world. In a royal court ruled by lies and power games, he is no longer the demon to be feared… yet. His mother concealed his identity on the day he was born, and a river of blood flowed for his sakeNow he will learn how to pull the strings in court as its prince, and train to ascend the throne and become the most powerful mage the empire has ever seen.The world thinks it killed him. It only gave him a reason to return.

mc gets transmigrated to Fallout New Vegas with the merchant system. let the questionable adventure begin.

Freely traverse between the city and the abyss, cultivate a demon legion! Command demonic talents!My name is Bai Yan, from that day on... one of my souls possesses two identities.I am a demon! Also a human!When I am good, I benefit the world! When I am evil, there are corpses everywhere!

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?