You are right. The girl transitioned into a male. He confirmed it himself with a comment on a version of this vid on PH (purged). He said it wasn't the greatest memory, since he couldn't afford HRT.
Or the girl in the video could have transitioned to a man. It's not really clear who of the two underwent a transition, both would be quite a loss considering the girl has an amazingly tight and feminine body and the guy has an impressively big dick. Maybe he just meant the transition from one position to the next?