Once, there was a man feared above all as the ultimate hitman. His codename was "Nightshade."

A master of a thousand lethal techniques designed to sever the human nervous system, he was a phantom who stripped his targets of their five senses before delivering the killing blow. To the criminal underworld, he was the undisputed "Reaper."

But that man is no longer in this world. Choosing to defy his orders to protect a single young girl, he was mercilessly eliminated by his own organization.

Seventeen years have passed since his death... and no one could have possibly imagined the truth. The legendary Reaper has been reincarnated and is currently living an ordinary life as a high schooler.

Now, it is one teenager up against an army of elite assassins armed with deadly, supernatural "Traits." To rescue the girl who remains imprisoned by his former syndicate, the Reaper is about to wage a one-man war against the largest dark organization on the planet!