Mujina into the Deep, Vol. 1 by Inio Asano

[Viz] No life but the one you make, no rights but the ones you take! In the near future, human rights aren’t guaranteed, but they are for sale. Without your rights, you’re just a mujina, with no place to call your own and no laws to protect you. But if the laws don’t apply to you, you can do anything you want. You just need the skills to back it up. And if you’re really good, you can really make a killing. Terumi Morgan bitterly accepts that he shouldn’t expect a lot from life. He just wants to meet his deadlines at work and watch his porn in peace. But then an unexpected sick day sends him on a collision course with two people who will change his world forever—a runaway kid and a thirtysomething mujina assassin. Suddenly life is expecting a lot from him.