Because You Cheated

The story of the protagonist's struggle after her fiancé is stolen by her younger sister begins now!

Liche has a fiancé who is the same age as her.
Her fiancé, Harkin, is the eldest son of the Marquis of Hachette, and is the picture-perfect man with handsome features and a brilliant mind. He is kind to Liche, and polite and cheerful to her family.
Her friends and schoolmates envy her, and Liche believes that even if it is a political marriage, she will still be able to build a good family.
But then...
One day, she witnesses her fiancé, Harkin, and her sickly younger sister, Lilia, secretly cuddling in the garden.

The story of the protagonist's struggle after her fiancé is stolen by her younger sister begins now!