Ginji Iwakura is Sasami's father and works as a novelist. Like Washu, he is from the Magical World, but is of a higher rank, thus he has magical powers. He has forbidden Sasami from using her powers, mostly because he loves her and wants her to grow-up like a normal girl, but mostly out of concern of the Chief Sorceress.
Ginji's first name is based off of Ginji Kawai from the Magical Project S series. Like Ginji Iwakura, he also played the same role as Sasami's father.