Fuka Gakuen is a combined school with classes from primary through to senior high. In Fuka Gakuen, there is a rumor that a mysterious monster had once appeared, and that the only counter-measures against the monster were girls called "HiME", who possessed the abilities of HiME (Highly-advanced Materializing Equipment). Mai is a transfer student unaware of this rumor. However, she is suddenly told that she possesses the power of a HiME. After facing a few problems, she learns to live her life as a HiM