He glared back at him with so much intensity
"YOU THINK YOU'RE THE ONLY ONE WITH PEOPLE YOU CARE ABOUT!? THOSE PEOPLE OUT THERE? THEY'RE MY FAMILY YOU IDIOT-AND I WOULD DO ANYTHING FOR THEM!!!"
And with that-he used Dabi's fire. But-he didn't hit anywhere that could actually seriously injure him-he hit one of the burnt patches on his arm, one with no nerve endings. Enough to cause him a pressing distraction and let Kei go, but not enough to actually hurt him.