Bootsleg

At seven years old, Zen's parents, sister, and his own left leg were swallowed by the mysterious gloved entity only known as Shake Hand. And Zen's not the only one—in the seven years after, these "gloved hand" incidents have only increased, and others have lost families and limbs, too. But Zen is powerless to do anything about it...until the fateful night his eyes are opened and he once again comes face to face with the mysterious, murderous Shake Hand—and the artisan syndicate sworn to stop him, known as Bootsleg!

(Source: Kodansha USA)