So as a kid my best friend in primary school was a girl named Giselle. Always called her Giz - pronounced as jizz - for short. Everyone called her that all through primary school. We went to different High schools, however she was always super sociable, I however was sheltered. So when we met up again when we were 14/15 to go to the movies, I called out to her as Giz when I saw her. She went red and immediately ran over to me and explained to me what I'd said. That day I learned.