|Name||Set, Cyborg 0018|
|First Appearance||Cyborg 009 vs. Devilman episode 3|
|Species||Human (Mutant) Cyborg|
|Powers||Accelerator, Self-Repair, Psychic Powers|
0018 is a slender, incredibly fair-skinned young man with short, pale silver hair, the long asymmetrical fringe of which falls over his right eye. Similarly, his eyes are a pale blue. Unlike the other High-Teen cyborgs, he does not wear the uniform (except in art books) as he was in a coma for most of his appearances, and was kept naked in a containment tube. Beneath his synthetic skin is a mechanical skeleton with wires hooked up to them with the only organic component left being his brain.
After merging with Atun, Set's eyes become more "demonic"-looking with contracted pupils and irises, he becomes more muscular, and he gains red bolt tattoos on his face. His body from the waist down grows black feathers not unlike the lower body of Devilman. After Atun takes full control of his physical form, he gains the demon's appearance.
Before his conversion, Set was gentle and soft-spoken who was fond of his older sister Eva, often having to rely on her. After the merger with Atun, the newly fused Seth/Atun hybrid was homicidal, and willing to kill anyone in his path. He also became turned against his sister, which necessitated her having to fight him, and was murderous towards her, with no qualms in injuring her in whatever way he could to gain the upper-hand.
Set is as an intentional mutant, a human born with special powers that can be exploited with cybernetics with Set having psychic powers similar to his sister including telepathy, telekinesis, and telekinetic shockwaves. As a high teen cyborg, 0018 is outfitted with an accelerator that allows him to move at mach speeds as well as a self-repair unit to restore systems, recover from injuries, as well as nearly unlimited stamina for his accelerator. After merging with Atun, his powers are greatly enhanced, with his psychic powers now featuring a disruption function to other psychics including Eva.
Set along with his sister Eva and Abel were born in a Black Ghost secret base in Canada with Set being specifically developed by Black Ghost to be part of an esper line as well as the High-Teen Number cyborgs. Unfortunately, the process rendered Set sickly and he ended up in a coma. Dr. Adams' however exploited this however for his Cyber Daemon project. Set ended up being the test subject and would be fused with the demon hero Atun when given the right opportunity.
Eva believing the process would cure her brother's condition went with Dr. Adams' plans going to Japan as a high school student and abducting Miki Makimura to bring Akira Fudo (also known as Devilman) to complete the fusion with Atun. When Set did wake up however, he was overtaken by Atun's influence killing Dr. Adams as he no longer had any use for him by telekinetically breaking his neck. Set would attack Eva before taking Atun's form.
In battle against Devilman and Cyborg 009, Atun and Set would be fused together into a gestalt form known as Azazel after Eva started a process that shut off the High-Teen Numbers self-repair functions. Azazel would slaughter his former teammates until Eva used her last ditch astral projection technique to reach out to her brother with help from 001. Eva's soul was able to successfully separate Set from Atun with Atun gaining Set's body while Set passes away with Eva following.
Set's name comes from the third son of Adam and Eve, as well as the younger brother of Cain and Abel, born after Abel was murdered. In the series, it was 0018's 'rebirth' as Azazel that caused the death of 0017 (Abel).
- Seth's design comes from the Ishinomori character Jun, a character said to be based on the teenaged Ishinomori appearing in the series: Fantasy World Jun, Blue Zone, Agartha, 7P, and The Magical World of Jun.
- The character design also appeared in a few other series by Ishinomori including Cyborg 009 and The Age of the Great Dinosaurs.
- In the early character concept art, 0018 had worn an altered High-Teen Cyborg uniform with the red and white portions reversed and the overall design being similar to the original manga 00 cyborg uniforms, simply with the addition of glowing white seams all over it and red buttons on the knee and toe portions of the boots.