A transformer refers to a man or woman who has decided to change their gender that they were intended to have/born with; in the process of or has completed their transitioning.
Girl : "Did you see the news on Caitlyn Jenner"?
Boy: "You mean the news on Bruce Jenner the "transformer"?
HOW THE HELL DO YOU NOT NO WHAT A TRANSFORMER IS DO U NOT PAY ATTENTION TO THE WORLD R U FUCKING BLIND NO!!!! YOU CAN EVEN STILL HEAR ABOUT A TRANSFORMER EVEN IF UR BLIND U JUST MUST BE FUCKTARDED