ZETMAN: Katsura Masakazu Tanpenshuu

The manga is a collection of 4 oneshots, published between 1989 and 1995 in Shueisha's Weekly Shounen Jump magazine:

ZETMAN(特別編集オータムスペシャル); Shounen Jump 1994, Special Autumn issue
Jin Kurono's father is dead, so he has been raised by his mother, who taught him the sense of honor and justice. But she died killed by a car, which ran away after the accident, leaving a scar in Jin's heart. Now, he's 23 years old, and he is the programmer of a new game: Zetman. Upset with the fact that there is no justice in the real world, he turns into his own superhero Zetman, to fight against crime, but with hard methods. To advise him and support him, he will always have his friend Sachiko Shirai.

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