He was born by Anti-Wanda in the episode "Anti-Poof". The first sentence he said was "Hello Clarice, I mean mother." He wants to destroy Poof because Foop doesn't want to "share the spotlight" with him (he wants to be the only baby born in thousand of years, not the 2nd.) His name is "Poof" spelled backwards which is because they are total opposites. He thinks Poof's name is more masculine than his own.
Foop didn't want to share the spotlight with Poof and aimed to destroy him, he set out to find Poof and conquer the world, not before absorbing the magical power of the Big Anti-Wand in Anti-Fairy World and using his magic to turn Anti-Fairy World into a cute storybook land, and the Anti-Fairies (including Anti-Cosmo and Anti-Wanda) into stuffed animal like creatures. Foop also destroyed the planet Burger World when he learned they were selling Poof toys in their "Peppy Meals".
Tracking Poof to Fairy World, Foop proceeded to drain away all the color and magic from the landscape and Fairies, even Jorgen. Luckily, Cosmo, Wanda, Timmy, and Poof managed to escape to Earth before they could be affected. Foop soon learned Poof's location and came after him, the two fought a pitch battle and seemed equally matched, however, Poof and Timmy noticed that Foop was extremely tired due to not having a nap, claming he did not need them. Thinking quickly, Timmy summoned the Fairies and Anti-Fairies (and one Burger World Employee), who proceeded to sing a lullaby, which successfully made Foop fall asleep, causing him to fall into Anti-Wanda's arms.
Timmy then figured out, that since Foop was the opposite of Poof, and bad things happen when Poof cries, that good things happen when Foop cries, Poof proceeded to swipe Foop's bottle, causing him to cry, which reversed all the damage he had done and reverted everyone back to normal.
Foop was then locked away in a maximum security time-out playpen in Abracatraz, but vowed to escape and seek his revenge against Poof.
Role in the Series
Foop, despite his father being a member of the Dark Dragon Empire, decided not to be a Dark Dragon servant because of the family's sour relationship. He is intending to join the Villain League as he knows they are the best choice available.