Wielders Of Mana: Secrets of Twilight

Hi, I'm Lillian Christos, and I'm a witch. I study in one of the most expensive, most reliable, and most private school of Magic ever known in the magic community. Naturally, that had to make me one of the bests, right? But no, not really. I wasn't that good. In fact, let me tell you a not-quite-secret - I was the worst. My powers were fine when I was young, but when I turned ten years old, my magic suddenly... weakened. No one knows what happened. Not my step-mother, Tanya, who used to be a really killer witch when she was a virgin, or my dad Simon, the most politically powerful senator in office, and the guy who was way too handsome for his age.
While my academics grade were set, my Magic grades were a struggle to handle. I've had numerous tutors these past 6 years, including my best friend, Iolanthe, and even my younger, eleven year old sister Scarlett. But I'd only been able to pass with the worst grades in high school that I'd might as well be a grade-schooler.
During the start of the junior year, Iolanthe and I added a new student to our small group of friends. A British girl who not only took the words "Angelic", "Beautiful", and "Elegant" to a whole new level but managed to surpass the best students, too. And she offered to tutor me! How cool is that!
But something is odd about her. Something different. Something... dark... Inhuman. She could be a Black Witch, a servant of corruption and insanity. But no. She was far too young, and no Black Witch or Wizard in history had ever entered a Magic school. No one could bypass the hundreds of guards and teachers.
But then again, I couldn't say. Especially when every time I stare out the windows of my dorm, of the school itself, I couldn't help the feeling that something was staring right back at me. And I had a feeling it was doing more than just staring.