It was so fast that it was the pain in his lips that made him realize what just happened, a weird tickling staying in his mouth just beside the cut that started to taste metallic.
Kirishima covered his own mouth with a hand, staring at him in shock, a thread of blood falling down to his jaw, and he copied the gesture, hiding his mouth while frowning because of the pain of his gum caused by the clash of their teeth.
Yes, it was an accident, but he couldn't help the boil of his blood attributing to anger.
He saw him swallow, not even caring the blood falling from his lower lip to his hand and all the way to his forearm, but he himself cared about his own blood running down to his neck and disappearing in his shirt.
He didn't felt the strength to complain or insult, overwhelmed by the rare combination of harsh pain and softness, and he tried to make his eyes do the job for him, glaring with annoyance because of the accidental clash of their teeth with their mouths between them and the closeness that he kept to his face, not even getting away or off of his body.
But Kirishima didn't move, his tiny eyebrows rising a bit and his hands falling a tad from his face, letting him see a flash of his tongue going over the cut. He didn't know he was staring until it was too late, Kirishima's clean hand holding his cheek. He got his hands out of the way to protest, not even finding the words when he received a soft kiss against the cut, against his lips.
It was very fast again, too much for his liking, and he realized the horrible heat going through his face, reflecting itself in Kirishima's face.
"… I'm sorry."
"Shut up" he snapped, this time closing the distance himself.