Ferrid's manga / #storybook(22)

Mc is reincarnated into a story book world as the sister of the angelic Villainess. The mc positions herself as the forerunner in the fight over the successor seat and almost has it until she learns she must be married to inherit the position. Unfortunately, her potential suitor has been stolen away by her sister who plots to steal everything from our MC. To stop that, the mc proposes a contract marriage with a more eligible man.