Elf Tensei Kara no Cheat Kenkoku-ki - Chapter 9Book 2: -1: Negotiations

Feng Lingxi was the traditional family’s head mistress – a person with a charismatic yet sly personality with the ability to attract people easily to her side, and having the potential to take someone’s soul away. Crossing across boundaries from a decade ago to now, a world that gives woman full respect and acknowledgement….

Don’t be fooled by her, because she was someone who would act obediently in front of a crowd but, stabs them in the back when necessary! Disguising as someone that would gain her trust and belief! That was why the Emperor of Xian started doting on her, allowing her to become absurdly daring to do whatever she liked. This made the Empress speechless to tears.
That would be the cause of the kingdom’s downfall in the near future…

- Description from Novelupdates

Growing up in an orphanage and surrounded by poverty, Leo never expected anything good from life. Everyone around him had abandoned him, forcing him to survive as a thief. Yet, fate had other plans.Caught by mysterious figures during a daring theft, Leo is forced into accepting a perilous mission. Transported to a strange, magical world, he confronts terrifying myths he had never believed were real.Suddenly thrust into a brutal, nightmarish battle, Leo hears a feminine voice, filled with authority and danger:“Are you worthy to be my Master?”In that moment, his life changes irrevocably—transformed in ways he'd never dreamed.And the cruellest twist?He's the only human participant in this deadly game. With just one champion at his side, Leo must navigate and survive the merciless battles ahead, relying on his skills to fight, endure, and above all… to steal.But remember, this is just F—

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