I am an older sister who always had precious things stolen by my twin younger sister, and in the end even my fiancé was taken from me. And for some reason, I was berated by my fiancé as a bad sister who bullied my younger sister. But then, it turned out that my younger brother was plotting something sinister all along...

We were twin sisters, daughters of a duke. However, a dark older sister and a bright younger sister... the younger sister was sociable and loved by everyone. I was introverted and quiet, and everyone loved my younger sister. When my younger sister complained that her older sister bullied her and wouldn't return things she had lent, everyone believed her. And I was chosen as the crown prince's fiancée simply because I was the eldest daughter, but... "For the crime of bullying my sister Ariana, I hereby break our engagement!" For some reason, I was deemed the bullying older sister by the crown prince, our engagement was broken, my sister took my place, and I was banished. However... I never bullied my sister or stole anything. It was always my younger sister who did those things. What action does the younger brother, the only one who cherishes his kind older twin sister who was always oppressed, take against this unreasonableness...?