OP, just because you're mad that this fellow cheated on your sister with a (so he thought) 13 year old girl (say's a lot about your sister), that is no reason to make a scene and upset the kids on a bus. You could have potentially given an old lady a heart attack. They could have developed anxiety problems from your actions. If you wanted to do something about it, you should have waited for the prick to get off the bus and uppercut his face. Hell the police would've probably given you a slap on the wrist. I'm sure they don't mind seeing douches like that get their comeuppances.