There was once a doctor fixated on creating the "ideal human being." After the doctor's death, his fabricant creations start attacking humans in order to attain the perfect body. When Ashibi Yao's entire family is murdered by these fabricants, he sets out on a journey of revenge accompanied by the doctor's final creation, Fabricant 100.
 
(Source: MANGA Plus) 
Note: Chapter count includes a Special Side Story: Redundancy (蛇足) and the One-shot Fabricant 100 (人造人間100) bundled in the 5th volume.

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