So the protagonist didn't become the legendary Super Saiyan after all. Guess he'll have to keep training... or watch his imouto get killed by an alien overlord or something.
I'm actually kind of happy about this. It kind of takes me out of a story a little when there is just main character plot magic, so it's a little refreshing to so see a romance where the main character isn't an omnipotent god shapeshifter. Coolio.