Funny, I wonder if he told all his friends that he felt your boobs? We had seat belts, but Mom never made us wear them. Mom did employ many arm saves though. I remember Dad had a Cougar. As a child I would often take a nap right next to the back window while Dad was driving.
He probably did tell all of his friends. That was the second reason to do it - to boost his status among his male friends. That may have worked but he had trouble getting dates for the rest of the year. Girls talk about their experiences too and, once we started comparing stories, he carried the nickname “groper” for awhile, though I’m not sure he ever knew that.
Looking back, life has to be very tough for teenage boys with all of the stress caused by hormonal changes and peer pressure and little or no knowledge about how to handle the complexities of relationships. I’m happy to not have to be a teenager ever again and happier still that I didn’t have to be a teenage boy.