Pretear (2003)

Himeno Awayuki was a normal sixteen-year old girl until her father married a woman who happens to be rich. Since then, she has been perceived as an outcast by both her new stepsisters and her classmates. Later Himeno finds out from seven men called the Leafe Knights that she is something called Pretear, a girl who has the power to merge with and control the nature of the elemental-oriented powers from the Leafe Knights and stop an evil being called the Princess of Disaster.