Histerias is the commander of the seventh fleet attached to the Mazone's permanent Milky Way base; Mimay discerns she is a high official. Histerias is the pilot of the ship that brings the emissary Meizo to the Arcadia, but manages to escape when that ship is destroyed. Harlock intends to allow her to leave peaceably enough, but the revenge-minded Tadashi chases her down and destroys her plane nonetheless. His own fighter damaged by shrapnel from the explosion, Tadashi seems to see Histerias still alive and floating towards him in the emptiness of space, but seeing as the slowly asphixiating boy was quite out of his head with panic at the time, it's quite likely that her seeming survival was merely his paranoid delusion.