Blue Square leader during Yellow Scarves-Blue Square conflict that happen one year ago.
СonflictIzaya giving him information about Masaomi girlfriend Saki to him & later on Blue Square members under his command kidnap her & torturing her to lure Masaomi. But Kadota & his gang saved Saki thus defecting from Blue Square. Izumii & other top members are arrested by police after Saki give statement about his kidnapping & torture.
Previous Blue Square leader are Aoba, his younger brother.
Voiced by: Atsushi Imaruoka