The Sound of a Gun - Reader x Kuroo Mafia Au

Y/N works alone. Strickly alone. They help no one unless it helps them. Because of this, they become sadistic and detached from the world. After doing a job for Tetsurou Kuroo, the leader of Nekoma, they willingly go back to his base with the sole intention of causing trouble, but little do they know that this is the first step of breaking down the walls they spend so many years building up...
TW: blood, death, violence. (I'm not going to put a mature rating on this, so tread carefully if you're on the younger side).