Izuna Endō serves as the younger twin brother and co-pilot to Shizuna Endō aboard JUDA's non-combat Machina Deceive, specializing in electronic warfare. He mirrors his sister's physical appearance almost exactly, featuring chocolate brown hair in a neck-length bob with fluffy bangs and brown eyes, leading to frequent confusion between them. Key distinctions include his use of standard Japanese speech patterns, contrasting with Shizuna's Kansai dialect, and his JUDA uniform of a black suit, light blue shirt, and black tie.

Personally, Izuna exhibits a shy, reserved, and serious nature, standing in direct contrast to Shizuna's brash impulsiveness. This cautious demeanor influences both his approach to responsibilities and his hobbies. His primary specialized skill is programming, directly applied in JUDA operations.

Despite sharing a childhood involving frequent relocation across Japan and being born in Tokushima Prefecture, Izuna does not possess a southern Japanese accent like his sister. Official records list his height as 157 cm (5'2"), though artistic depictions sometimes show him marginally shorter than Shizuna.

Within JUDA, the twins operate strictly as a unit. They deploy in the Deceive Machina for reconnaissance, electronic countermeasures, and joint operations with military forces, such as coordinating with the Japanese Maritime Self-Defense Fleet to locate enemy Machina pathways. During missions, Izuna often acts as a moderating influence; he notably intervened to halt Shizuna's physical assault on Kouichi Hayase during a confrontation at JUDA headquarters.

The Deceive Machina's capabilities center exclusively on electronic warfare, aligning with Izuna's technical expertise. His consistent role involves providing tactical electronic support alongside Shizuna during JUDA's engagements against antagonistic forces.