Before this.
After Goku's body was pricked by the Bell Orchid Grass, he fell unconscious. His mind, meanwhile, sank into an unbelievable alternate dimension...
He turned his head and saw his own... tail!
"Huh? Why do I have a tail? I... could I be..."
Goku raised his head and looked everywhere for a mirror, but he was in the middle of a vast forest—there was no mirror to be found! After much effort, he found a pool of clear water. Looking at his reflection, he saw the figure of an adorable little boy!
"Me? Goku? I'm a little boy? With a staff on my back? And a tail behind my butt?"
Goku stared at his appearance in shock, but then he suddenly could not remember what he was supposed to look like!
"This staff is the Adamantine Staff, right? It seems... it can keep extending and shrinking..."
When Goku shouted, "Extend!" the staff suddenly lengthened, shooting out dozens of meters at once. When he called, "Shrink!" it immediately shortened, reducing itself to just over a meter long.
He curiously tugged at his tail. Suddenly, a sensation like an electric shock swept through him. Goku's entire body went rigid, and he crashed stiffly to the ground!
"Wuwuwu... So my tail... is actually my weakness?" Goku sadly realized that he had somehow become a pitiful child, and everything was part of his past!
"Well, well? There's a strange boy here." A sweet, adorable voice sounded beside Goku's ear. He turned around and saw a golden-haired girl looking at him provocatively.
"Hey, boy, do you know where there's a 'Dragon Ball'? It should have several stars on it and be about this big?" The girl gestured with her hands, indicating something roughly the size of a volleyball.
Goku suddenly stiffened. "A Dragon Ball?