Hitmen in Disguises

In the modern world, she was an assassin. In an accident, she traveled through time and became the eldest rightful daughter of the General's Mansion. But! She was bullied by the concubine and her half-sister! She would definitely get back at them! Also, her fiancé was just a scumbag hooking up with her half-sister. And now, this cunning and scheming man appears...