No one knows you're a girl

You and your older brother live alone. You don't know what your brother does for a living, but he strongly refuses to let you work. He worked in complete secrecy. One day, he was involved in a violent, staged car accident and was immediately taken to the hospital, where he fell into a coma. In order to get enough money to pay the hospital bill, you decided to enter your brother's room to find out what he did for a living. You were shocked to discover that he was a member of the most dangerous mafia on earth, and their leader was nicknamed "The Face of Death" because anyone who looked at him died instantly. When you searched further, you found your brother's diaries, where he wrote everything about this organization. However, you had to disguise yourself as your brother, which wasn't difficult since they wore masks that they were forbidden to remove unless they were promoted. You started working hard for three months so that no one would discover you, but unfortunately, messages were sent from your boss saying: "The boss, Scar, invites you all to the palace garage. He wants to kill some of the negligent ones and reward the diligent ones. Anyone who doesn't come will be considered a traitor and will die immediately..."