He is voiced by Takaya Hashi in Japanese and Richard Epcar in the English dub.
In the past, scientists attempted to harvest the Earth's gravity for energy, resulting in the devastation of the surface and a reverse of the gravity field, causing much of everyone and everything to be sent floating into the sky. As a result, all surviving "inverts" move underground so they won't float into the sky. Izamura rules over the Aiga society, keeping its citizens under constant monitoring and forbidding them from looking at the sky. Unknown to the citizens of Aiga, it is in fact the Aigans who are the true inverts, a fact which Izamura keeps hidden from the citizens.
At some point, a boy, Age's, father crafted a flying machine with an invert named Lagos. Izamura, however, had Age's father assassinated and Lagos imprisoned, where he later died. Years later, another invert, Patema, arrives in Aiga and meets Age. The two learn that by gripping each other, they can reduce the rate from which Age can fall. Izamura, discovering Patema with his numerous video cameras, orders he captured. He reprimands Age and takes Patema to a giant governing tower, trying to force her to confess where the other inverts are located. He threatens to release Patema into the sky, and then imprisons her in the top floor with ony a plate of glass separating her from the sky.
When Age returns to rescue Patema, Izamura orders his assistant Jaku to execute him. Jaku hesitates, allowing Age and Patema to escape. Because Patema has an inverted weight attached to her leg, she and Age float into the sky in front of everyone. Izamura tells the public that Age had died in an accident. Jaku, meanwhile, discovers that Izamura had ordered Age's father killed. Patema and Age return and drift into the large hole leading to the other inverts, but Izamura follows them.
Izamura plans to have the inverts killed, but Jaku turns against him. Izamura shoots Age in the leg and nearly Patema's friend Porta, but the floor of the shaft shatters, revealing sky below it and exposing Izamura and the Aigans as the true inverts. Izamura "falls" into the sky, attempting to pull Patema with him, but is forced to let go when the remains of the flying craft collide with him, sending him into the sky to his death.
- Izamura can be compared with Judge Claude Frollo for the following reasons:
- Both had genocidal hatred on races that they despised (humans that believed to be "inverts" in Izamura's case and gypsies in Frollo's case), in which one of the protagonists(namely Patema) appeared to be one of them.
- Both had a lustful and unhealthy love on a female member of the race that they despised (Patema for Izamura and Esmerelda for Frollo).
- He eventually suffer a symbolic but ironic death (Frollo falls into molten lead that symbolized hell, place where the damned souls would be punished for good whilst Izamura ended up levitates to the sky where he believes it as the place where the sinful ones would died.)