I'm The King of Business & Technology in the Modern World - Chapter 3: Signs of Legitimacy

Have you ever thought a monster that has a job of a summoner and a tamer

what should it call itself Monster Summoner? Monster Tamer? but he itself was a monster too

Watch as our mc travels the world as an reincarnated human who turn into a monster

In a world where magic is a science, Siobhan is a genius.But even geniuses need schooling.When Siobhan stumbled into the theft of a priceless magical book, she thought her dreams of becoming the world's most powerful sorcerer were destroyed.But then a mysterious spell changed her life forever...Siobhan is now wearing the body of a strange man and has a new identity—Sebastien. With a new chance for a new start, she allies herself with a local gang—secretly a revolutionary party funding itself through crime. Now, she is bound by vow to repay them in magic and favors. But as Sebastien's reputation begins to bloom, and Siobhan's old enemies still lurk in the shadows, she quickly realizes that the secrets of this world are deeper and darker than she ever could have imagined.Forced to juggle the two sides of her double life, Siobhan is determined to uncover the truth and take control of the name they gave her - The Raven Queen.

Luo Zheng is at the bottom of the Luo Clan hierarchy, despite his family being the founders of a power refining technique that could instantly defeat any opponent.

One night, enraged by unfair treatment from a family steward, Luo Zheng burns the family records. In doing so, the hidden magic in the book engulfs him and Luo Zheng becomes a new skilled fighter. Fleeing his home and despicable clan, Luo Zheng must learn to harness his powers to rescue his younger sister while his own cousins are on his pursuit.

- Description from Novelupdates

“Jiang Fan, I regret it!”When Xu Yining realized that the useless fiancé she would rather die than marry had taken her sister as his wife and transformed her into a powerful empress, she was filled with regret.If she could do it all over again, she definitely wouldn't have petulantly let her sister marry in her stead!