Camullita Empire's top magician and perfect princess, Arbella, falls ill with an unknown disease one day. On a night when she was writhing in terrible pain as usual, she dreams of her future. There's only one person laughing there, her step-sister Judith! How could a lowly slave-born girl like her dare to take away my glory?! Arbella even tries forbidden magic, but she eventually meets a tragic end. Shedding tears for a moment upon waking up from her dream, Arbella begins to make a plan to survive. 1. Keep her step-sister, who will become her future enemy, close by. 2. Obtain the guardian knight of Judith, who will eventually become a sacrifice for forbidden magic. Fortunately, the plan is smoothly executed, and the two of them are within Arbella's grasp...