In present-day Tokyo, 17-year-old Akira Nakamura uncovers a revolutionary system enabling humans to upgrade their body parts through combat. As Akira learns to master his newfound abilities, he is thrust into a perilous world where enhanced individuals vie for supremacy, each clash unveiling the potential for extraordinary power.

Whilst grappling with this new reality, Akira strives to comprehend and control his evolving powers. He finds himself embroiled in the escalating conflict between those who embrace these upgrades and those who fear them. With each encounter, Akira grows stronger, unlocking new abilities that push the boundaries of human capability.

However, as he delves deeper into this realm of enhancements, an underlying tension looms. There is a hidden cost to his transformations—one that could lead to personal harm and unforeseen consequences. This risk remains veiled in mystery, even from Akira himself.