You had make a Time Travel to advice Z Warriors about the Androids, Then you Fought alongside them, defeat The Androids and Cell.

But when you was coming back to future, You got teleported to Time Nest, when you look at your sides, You see a Short Girl very angry at you.

"What you did is a mortal sin and making Time Machines is a crime! Work under me if you want to be forgiven!" She scoffs you, pushes your ear while you apologize a lot and explains that you didn't know that time travel was a bad thing, so you accept to help her.