Keep doing nothing(SLBC)
From Create Your Own Story
You remain still and silent you're continued submissiveness emboldens him further and he continues to run his hand up your thigh, until he comes into contact with your cock and balls. He pulls his hand away sharply gets up and pushes past you and heads for the front of the bus where he gets off at the next stop all the while muttering to himself. Everyone turns to stare at you and you start to feel self-conscious.
Do you?