Katsuki's Quirk allows him to secrete nitroglycerin-like sweat from the palms of his hands and ignite it on command, allowing him to create strong explosions. The more Katsuki sweats, the stronger his explosions become. If Katsuki overuses this power, his forearms will start to ache.Katsuki is a young man of average height, with a slim, muscular build, and a fair skin tone. He has short, spiky, sandy blond hair with choppy bangs that hang over his eyebrows. His eyes are sharp and bright red.