In the premiere episode of The Fairly OddParents' sixth season, "Fairly Odd Baby", Timmy noticed that Cosmo and Wanda had been continually letting themselves get distracted by the sight of human babies. When asked why, they explained that it was because they wanted to have a baby of their own, but after the problems caused by Cosmo when he was a baby, all fairies had been forbidden to have their own babies (hence why they're assigned to godchildren). Anxious to put their problem to rest, Timmy wished they would go ahead and have a baby, leading to Poof's conception.
When Poof was born, the Anti-Fairies and Pixies tried to steal the baby, as a baby fairy's magic is uncontrollable. Timmy desperately takes Poof in an attempt to flee, but finds that when Poof does certain things, strange results ensue. When he laughs, good things happen; when he cries, bad things happen; when he burps, lightning strikes the one nearest; when he hiccups, natural disasters happen; and when he breaks wind, reality itself goes out of control. Eventually, they used Poof's powers against the Anti-fairies and Pixies. When they returned home, Wanda wanted to find out the gender of Poof, so changing his diaper is the best way to find out. After using a water-gun, he is proven a boy, because boys prefer water-squirters. Poof's fairy color seems to be purple, hence his purple outfit.
In the episode "Hairicane", it was revealed that Poof's hair grows back soon after it is cut.. Strangely, Poof is shaped like a ball and has been since he was 'born', yet Cosmo's birth in "Fairly Odd Baby" had him shaped more like a human. Also, Poof is a new super sidekick puppy to Timmy, as Cleft, when he visited the Crimson Chin in "Chindred Spirits". There is also an Anti-Fairy named Foop, who was born soon after Poof as to give him the standard Anti-Fairy counterpart.
Poof likes to watch children's television shows. He also enjoys playing with the little children in the neighborhood with his dad, Cosmo. In "Wishing Well", it is shown that Poof will cry if Timmy leaves because he is used to him being around and loves him very much. The only word Poof said before he was named was "poof", hence the name. In the episode Poof has his first transformation as shaving cream. When Poof farts, reality itself doesn't bend. It just makes great transportation.
He has said only "Poof", "Mama", "Crocker", "Dada", and "Timmy", and also constantly giggles. However, since "School of Crock", he goes through a phase called "Pooferty" and can now speak in full sentences.
Poof is a round baby, not like his father Cosmo, who was, when he was a baby, shown early in the show as shaped normally, as in, shown human. His eyes and clothes are purple, which in the episode "Fairly Odd Baby" gave viewers the thought of what gender he could be. In the episode "Hairicane", it is shown that his hair can magically re-grow after cut.
- Cosmo, Poof's father, was the last fairy baby born before him.
- Poof has to go through 83 diaper changes a day.
- Despite being a main character in the later half of the original show's run and appearing in the live-action movies, Poof is oddly absent from The Fairly OddParents: Fairly Odder.