PROLOGUE
A loud gunshot echoed through the surroundings.
Birds scattered in panic inside the abandoned warehouse as the body of an old man collapsed onto the floor. His head had been blown apart, exposing the flesh and brain inside. Blood spread across the concrete floor like water spilling from a broken container.
Standing off to the side, a young man covered his mouth, fighting back the urge to vomit. He wore a pair of oversized eyeglasses, an oversized blue long-sleeved shirt, and black slacks.
His legs trembled uncontrollably as he stared at the old man's lifeless body. He was so terrified that he was on the verge of fainting, and he nearly dropped the cellphone in his hand.
"Cut off his head and send it to him," his companion ordered coldly as he wiped the blood splattered across his face.
Unlike the young man, he remained perfectly calm.
He had just killed someone, yet there wasn't even a hint of sympathy on his face. Like a robot, he remained utterly emotionless.
He truly deserved his name—Ken, the strongest and most merciless assassin in the Dark Organization.
"Th-then, wh-what about his body? Should I—"
"Burn it," Ken replied curtly.
He was about to leave when the young man suddenly grabbed him by the arm and called out his name.
"K-Ken..."
Ken's expression darkened.
He turned his cold gaze toward the young man.
"Ken?" A sarcastic grin slowly spread across his lips.
"Did you just call me by my first name?"
He had never allowed anyone to address him by his first name, especially someone he barely knew. It wasn't a matter of being petty or unfair. Rather, being known by that name only served as a reminder of the monstrous nature he possessed.
To him, Ken was more of a title than an actual name—a badge that represented the monster he had become.
"Listen, kid. I didn't help you kill that old hag because I accepted you as my new partner. I killed him because my gun was craving blood. Get your act together. I can still kill you if I feel like it."
Embarrassment and fear were written all over the young man's face. Slowly, his grip on Ken's arm loosened.
Ken shook his head in disapproval before turning away and continuing toward the exit.
*You've got a message.*
Ken pulled his cellphone from his pocket and checked the notification.
A photograph of a man wearing a black suit appeared on the screen. A large red X had been marked across the man's picture.
Beneath it were two words:
**—Kill him.**
Ken's grip tightened around his cellphone.
He didn't know who he was. He had no name, no family, no past, and no future.
Everyone in the guild called him Masuta or Kage—the Shadow.
A heartless, inhuman assassin who killed out of gratitude.
This was his life.
The path he had chosen offered no escape, no turning back.
There was only blood.
Blood and death.