Toaru Majutsu no Index - Volume 14, Chapter 1: A Too-Quick Rate of Change. In_a_Long_Distance_Country.

"In her previous life, she is used by her first love to send her own company into the tiger's den. She becomes bankrupt, gets kicked out of the house by her father, and becomes the target of ridicule by the family. Worst of all, she believes her best friend's lies, thinking that everything was done by her ‘husband’. Under her best friend's ploys, she almost kills him and is ultimately sentenced to prison, where she dies of depression.

Son of a bitch! I just finished this godawful fantasy novel, and now I'm knee-deep in it – as David, the disgraced son of the Solarian Empire's top general! Talk about some twisted cosmic joke. But hold on a damn minute... maybe this isn't all bad. Armed with the knowledge of that trashy plot, I can become the ultimate shadow player, an overlord perhaps. Screw the damsel-in-distress harem too – it's time to pull the strings and become the real power behind the throne. This isekai might be a steaming pile, but I'm rewriting the ending with a little more... Debauchery (wink wink).

Shi Yu, an Archaeologist and Mythologist, crossed into a foreign world where Noble Beasts were the mainstream.

The Empress does not grant my resignation.