Bubble Boy is a superhero that Gil pretends to be in the Bubble Guppies episode Super Guppies. Bubble Boy is the first sidekick of Guppy Girl and one of the three defenders of Big Bubble City, and also one of the two main stars of the comic book series The Super Adventures of Guppy Girl and Bubble Boy, which is where Gil got the inspiration to pretend to be like him.
In the retelling of the comic book in the episode, Gil (aka Bubble Boy) works at a news and magazine stand in Big Bubble City. But when he hears his Bubble Phone ring, he becomes Bubble Boy and flies off to save the day with his mentor, Guppy Girl. During one mission, Bubble Boy and Guppy Girl were tasked with stopping the smelliest and evilest villain to ever attack Big Bubble City, Sid Fishy, from filling a cloud full of a concoction called Stink Sauce in order to make the cloud rain Stink Sauce all over the city. However, Bubble Boy was caught and trapped by Sid Fishy's henchman, Orange Ruffy, when he tried to turn off the pump inside Sid Fishy's blimp. But once Guppy Girl rescued him, he trapped Sid and Ruffy in a super bubble and hauled them off to Big Bubble City Jail while the blimp filled back up with Stink Sauce and was sent into the ocean by Guppy Girl.
His next mission came around when he and Guppy Girl had to stop Miss Goo-Goo from turning everyone in Big Bubble City into babies. However, Bubble Boy was turned into a baby and his partner had to battle Miss Goo-Goo alone until her little sister, Mia (aka Bubble Baby), came and helped save the day alongside her big sister.