You had been dared by Dabi to draw Smiley Faces on Tomura's hands, which you did. Tomura found out when the league burst out laughing when he walked in, he was pissed. Dabi: "(Y/N) did it! I have no part in this, totally not." Tomura: "(Y/N)! I'M GOING TO DUST YOU!" Tomura stomped forward, making you snicker as he still had the hand on his face