Tsuguna Jack
Gender Male MaleIcon
Age 31
Race Japanese
Species Cyborg
Hair Black, shaven
Eyes Dull brown
Height 6' 1"
Weight Middle-weight
Personal Status
Status Pending

Jack is an instructor at Osaka Gakuin #42. On the surface, he operates as a Physics instructor under the guise of an ordinary human, but to Divers and other cyborgs, he also leads advanced courses in software engineering, drawing on past experiences as a talented hacker.


Jack is slightly tall for his demographic, and his human body boasts a rather fit physique for an intellectual. His left arm, right hand, and entire body below the waist are completely cybernetic, having replaced his organic limbs after a traumatic event robbed him of them (see Personal History). A highly-convincing flesh polymer covers the cyborg components, making him look like an ordinary human. He shaves his remaining human parts to avoid them clashing with the hairless polymer.


Jack is a powerhouse of logic, his intelligence based mostly in hard facts and common sense. Rumors abound that Jack has a computer CPU hard-wired into his brain, but several instances of curious experimentation involving magnets and metal detectors have disproven these claims. This is not, however, to say that he's emotionless; actually, rampant exploration of the Internet has exposed him to a lot of funny multimedia, and he's developed a fine sense of humor (if somewhat memetic).

Attitude about ClassesEdit

Jack's time as an instructor is not to be wasted; he treats each class as a chance to bring knowledge to his students and nothing else. Kids who misbehave or slack off are dealt with harshly, cheaters even more so. There have been instances when he's even ejected students from his classes entirely. Anyone who does their work well and respects his class and the material he's teaching, however, will find that he's that much easier to handle as a teacher.

Personal HistoryEdit

Tsuguna Jack was originally a human criminal who excelled in computer hacking. Early in his mid-20s, however, he had the misfortune of being caught after siphoning a considerable amount of money from a man who turned out to have ties to the yakuza. Jack was hunted down, tortured, his belongings claimed from him, and then left for dead. Only the intervention of a certain benefactor (whose identity is yet unclear) saved his life, but even after being hospitalized and treated, most of his limbs had begun to atrophy and had to be amputated to prevent disease from killing him outright.

After being stabilized, Jack was interrogated for several other cyber-crimes he had committed in the past. The law was content to sentence him to a life of helplessness in a hospital, but Jack begged for a chance for redemption, desperate to escape being left an invalid. He vowed to repent for his crimes, to mend his ways and use his knowledge of computers for good; these pleas largely fell on deaf ears until a certain party representing Osaka Gakuin #42 (again, actual identity is undetermined, though likely the same person who saved his life) considered his bargain. Jack's freedom was negotiated on the condition that he would honor his word and become a teacher for OG#42.

As part of his rehabilitation, Jack was outfitted with cyborg limbs to replace those he had lost. To avoid drawing too much attention to himself, he was granted a request to have the prosthetics masked with a skin-like cover. At first, Jack was simply a Physics teacher, but when he managed to back-trace a cyber-attack on the school's computer network, he was given the opportunity to teach advanced computer courses as well. He has maintained this position for several years now and remains fully loyal to the institution that allowed him to rebuild his life.



  • Jack rarely speaks about his family before OG#42, and even then never by name. He has, however, mentioned his mother, his father, and an older brother in the past.

Friends and AlliesEdit

  • Although he hasn't had much contact with the world outside of OG#42 (save for the occasional online communique), Jack gets along pretty well with most of the school's faculty and with the student council.

Rivals and EnemiesEdit

  • The yakuza who robbed and crippled Jack are an obvious mention, but he never brings them up. Rather than hating them, he actually harbors a subtle fear that they might learn of his survival and seek him out again one day...

Combatant InformationEdit

Jack is proficient with most light firearms and prefers to use them when possible, his weapon of choice being a modified handgun (one resembling a Sig Sauer) with an extended clip. In close range, however, he fits the bill of the proverbial Glass Cannon: though not very fast or resilient, he is exceptionally strong, skillful, and nimble. As long as he doesn't take a hit, he can tear through an opponent's defenses with ease, striking with pinpoint precision with his cyborg-enhanced strength.



  • 31 years ago: Tsuguna Jack is born
  • ~8-10 years ago: Jack robs a yakuza sympathizer
    • The yakuza capture and torture Jack, rob him of all his possessions, and leave him for dead
    • A mystery individual finds and rescues Jack
    • During recovery, most of Jack's limbs are amputated due to high risk of infection
    • After recovery, Jack is convicted of previous crimes
    • A representative of OG#42 negotiates Jack's release, under the condition that Jack works for OG#42 indefinitely
  • 7 years ago: Jack is fitted with cyborg limbs and begins work as a Physics instructor at OG#42
  • ~4-6 years ago: Unknown hacker attempts to sabotage OG#42's network
    • Jack traces the hack attempt to the perpetrator and restores network functionality
    • OG#42 allows Jack to teach specialized computer courses to select students

Ongoing ScenesEdit

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Completed ScenesEdit

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  • Jack's alias is derived from "amanojaku", the name of a Japanese demon who incites people to do wicked deeds. His full name, Tsuguna Jack, is written as "償 ジャック", using the Kanji for "atone", which refers to his history as a hacker.