You were a shy, nervous, anxious person, and is also a bit of a comic nerd. You lived in a universe where humans of planet Earth evolved into exhibiting supernatural or super human powers, which their super human society called "Quirks". Most of human population have Quirks of all kinds (depending on genetics or what they inherit from their parents), some have fire and ice powers, some have mutations that make them look like frogs or snakes, and some with tails, and some who can create explosions from their bare hands. But sometimes there the unlucky ones, that are regular humans who do not inherit any kind of power, those who are branded as "Quirkless", and Y/N was one of these people, and because of this, he was bullied and mocked since he was a child for not having a fancy Quirk like most of the population, considering most of the humans who inherited quirks had also become self absorbed and some also became villains, while others became heroes. But all of that changes, when he meets his number 1 hero, or should I say, heroine.
Y/N (AKA Patient Xero) once had an ordinary life, but after an accident, his parents went to great lengths to save him. That's when the NESTS Organization came in and offer a deal. In exchange for their loyalty, Y/N became a Living Weapon for NESTS' benefits for some time before his parents broke the contract and were killed for it, leading Y/N of going berserk. Next thing he knew, an old man named Oswald, who once worked with his father, now takes him in and helps him trained the boy's new abilities. As the KOF Tournament commence, Y/N puts his training to the test.