The Esper Saga
Leesa is an half-esper, daughter of Alexander. As such, she possesses potent Light based powers, such as Shields and Healing powers.
It has also been shown that she has some very powerful lightning style abilities.
She has also proven to be not too poor with the blade.
Leesa is an orphan, whose mother died in childbirth. And her father was killed, or so it was believed.
Leesa was saved by Michael Tragent, and put under the care of Maria, a housewife, and leader of a resistance organization against Baron von Savage. Later she was discovered to be a half-esper, daughter of Alexander.
Gehenna teaching the young Half-Esper, what it means to be an Esper.
While Leesa and Gwen appears to be teaching each other of what it means to be human.
Gehenna – She views Gehenna as an older brother, a teacher if you will. He is her link to the Esper world, so far.
Gwendolen – Her and Gwendolen has been through a similar experience, going from being human to no longer being able to believe it. Due to this, she holds on to her own humanity, through helping Gwendolen hold on to hers.
Michael – Michael saved, and helped take of Leesa in her young age. She adored him as a father.