A devious smile crosses the faces of your girlfriend and your sister as they make that one final change.
You are already somewhat of a freak so why not make it truly fun for them to watch.
Your body doesn't change any more but you find that looking at naked women no longer makes you interested. The posters around your room aren't the big breasted women you are so familiar with. They are hot hunky men.
Now you know this is not your normal because she said that only the three of you would know the true form. But you can't help being turned on by men.
It was at that point that your "boyfriend" came in. He was a big bear of a guy. The center on the football team. He had to be big and beefy and your seed gave him that added testosterone that made him even manlier. He was coming over for his fix. Riding your cock like a flag pole.
Your girlfriend and Jessica shut the door as they left you moaning in ecstasy and horror as you realized you liked men now.