MTL - The Earth People are so Fierce (Oh My God! Earthlings are Insane!) - Chapter 1772 raiders

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

The youngest princess of the country of Stellaus, Marietta, was betrothed in a political marriage to the General of the great militant country, Oltaire. General Belvant was often said to be strong, a fierce and terrifying god of a warrior. On the other hand, Marietta was a delicate flower of a princess. Everyone felt pity for poor Marietta’s situation, however, the truth was that Marietta found the General very dreamy… The story of a 30-year old General with a scary face (who was actually quite nice), and the tiny and adorable 18-year old Princess in their times of conflict and of lovey-doveyness.

The fiancée has betrayed, but how could she know that the man she looked down upon was in fact a prodigy with healing and martial prowess!

Her parents died in planned accident by her uncle. They used her in every way they can. They planned to sue her so she wont take her fathers company back. They want to destroy her life making her penniless. No one knows that she is the not the same girl who was played as puppet in their hands. Five years changed her a lot. Now she is a hidden genius still acting pityfull to take revenge.