DS (15) came home about an hour ago with blood all over his face in a right state. To cut a long story short, he'd had an argument with his girlfriend (also 15) who also happens to be black belt in karate and she apparantly kicked him twice in the face. Her father then dragged him out of their house and threw him onto the street where he's sprained his wrist upon falling to the ground.
I don't know what the row was about but I'm livid.
He doesn't want me to report it or do anything (I assume because he'll have to admit to being beaten up by a girl) but I can't just leave it.
What should I do?