The grinning devil (male reader x fem Itadori)

"Devil", that's what most everyone called him. After his house mysteriously burned down when he was little, resulting in his mother's death, things had never been the same. He told the police that a man with a volcano for a head did it and of course no one believed him but they couldn't find a direct cause for the explosion either so they labeled it as a "gas leak". However, humans being humans, everyone blamed him. Labeling him "The grinning devil" because after the accident he was seen with a wide toothy grin every time he was stressed, nervous, angered, or uncomfortable. But despite the ridicule and traumatic upbringing, Y/n Kusakabe was determined to become a hero in any way possible, find the one responsible for his mother's death, and make sure no one would go through what he had to ever again