Mario Rossi is a half Sicilian/Japanese assassin from New York who kills for money.
Mario Rossi is the child of an Italian mafia member and a woman from the Japanese yakuza, Yoshiko Rossi. Mario originally became a contract killer to earn money to help with his mother's medical bills, but it just became a job after she passed away. He keeps his mother's ear rings with him as a good luck charm.
Mario Rossi is the protagonist of the original one-shot titled Mario that was created by Masashi Kishimoto. It was first published in Shueisha's Jump Square 2013 No. 6, which was released in May 2, 2013.
After killing his old friend Tommy, Ken connected Mario with Saori, a young lady sniper. However, she refused to talk to him and would never let a man touch her. Ken worked as an interpreter between them. Mario stood as a distraction while Saori killed everyone in the room but one to be question. Mr. Lorenzo had heard about the partnership he had developed with Saori, and he wanted to hire them for Filippo Mancini. Though Mario and Saori had worked together for a while, she still didn't seem interested. That night, he offered her one if his good luck charms, the ear rings of his deceased mother, as thanks for saving him previously. She put the ear ring on and told him she was also a Libra.
At the meeting with Filippo, his man Pietro handed Mario a large stack of cash to leave Saori alone with his lecherous boss. Though guilt ridden, he rush inside to find Filippo dead. Peitro had also been shot and fingered Saori as the killer. Mario was then approached by Filippo's uncle, a high ranking mob boss. He was going to pay Mario half a billion to kill Saori and bring him her body, or his name would be added to the contract. He was devastated as to what to do.
Mario found Saori at the park where they first met. She drew her gun on him as he approached, and he told her that he was in love with her. They were interrupted when Ken shot Saori. Ken was going to take the cash for the job and kill Mario. He was saved when Saori shot Ken. Mario had to make the choice. Help Mario and get the cash, or be wanted by the mob. He shot Ken in the head, then gave gave Saori the other ear ring of his mother.