The leader of the Corruptors. At first, he is a "good" program, created by Dr. Inukai to manage and maintain the vast-growing ComNet. His contact with Yui made him want to "live", and later, to create a world where he could "live". Dr. Inukai, who saw the change in Grosser, decided to create the Correctors to restore him to his current status. When Dr. Inukai chooses Haruna as Corrector, Grosser, who was fascinated with (arguably"loved") Yui from beginning, manipulated I.R. and set Dr. Inukai in accident, so that Yui would be the Corrector instead of Haruna.

In the year 2000-something, a massive central network called Comnet links the computers of the world, forming a single global computer system. Comnet, designed to serve the interests of mankind, is managed by the supercomputer, Grosser. But when Grosser decides to take over the world, a savior is needed! 
 
A computer-illiterate girl named Yui Kasuga happens upon software program IR, which recruits her as savior of Comnet and pulls her into the virtual world inside. There, Yui is given the power to become Corrector Yui so that she can fight against Grosser and his evil Corruptors. 
 
Inside the virtual world for the first time, Yui must face one of Grosser's henchmen. She must also battle another of Grosser's minions, this time one who's infecting the e-mail passed between Yui and her friends. And finally, Yui and IR suspect foul play when Chef Kirch, a family friend who can never get his recipes quite right, has to face customers who've turned into ravenous zombies! 
 
(Source: Viz Media)

Mugihito is a Japanese actor, voice actor and narrator from Musashino, Tokyo. Mugihito was formerly credited under his birth name and also Mugihito Amachi (天地麦人).

In a world where computers handle everyone's daily needs, the worst has happened: the computers have taken over Humanity's only hope is Yui Kasuga, a not-so-tech-savvy school girl who accidentally discovers a living computer program called I.R. and is transported into a computer-generated world. Together with I.R., she must fight Grosser, the evil master control program. (Source: Tokyopop)