Pumbaa is a very lovable character and is very kind and tough. He deeply cares for his friends and is very protective of Timon. He loves bugs and longs for friends who won't abandon him. He is awkward in crowds, and sometimes displays child-like naivety which is sometimes confused for stupidity. Pumbaa in fact comes up with some very intelligent plans and insightful ideas, which Timon rapidly claims as his own. He also has a problem with his stomach which causes gas like results.
In The Lion King 1½, Pumbaa is the first to follow Simba back to the Pride Lands, but has great confidence in his friend Timon, so he runs slowly so that his friend can catch up.
Pumbaa, along with Timon, was first introduced shortly. Simba runs away and ends up in Timon and Pumbaa's territory where they save him from a pack of Vultures. Pumbaa quickly became friends with Simba and they spent time with Simba goofing off and playing around. When taking a walk Pumbaa hunts down a grub which leads him into Nala and a chase begins. Once Simba comes to the rescue Simba explains the lioness was his best friend growing up. Pumbaa and Nala become friends but soon thinks of Nala as a threat to his and Timon's friendship with Simba.
While resting shortly after meeting Nala, Pumbaa is informed that Simba has returned to his home. Pumbaa along with Timon joins Nala and Simba as they rescue the Pride Lands from the film's villain Scar. In the end, Pumbaa along with Timon moves into Pride Rock.
In The Lion King's second film, Pumbaa, along with Timon, become guardians of Simba and babysitters for Kiara. Pumbaa and Timon act as uncles to Kiara and are given the task of protecting her from danger. It's also obvious that Pumbaa has aged. He has gained weight and gained a darker skin complection.
In The Lion King's 3rd film (which is all about Timon and Pumbaa from a long time ago), Pumbaa and Timon are portrayed as the film's main protagonists. It was explained that Pumbaa was an orphan and mistreated because of his smell. He meets Timon after he was stalking him because he thought Timon being so little shouldn't be out alone. Pumbaa also noted that he came across a dream home that would be perfect for him and Timon which turned out to be the jungle they would soon call home.
When Simba returned to Pride Rock to battle Scar, Pumbaa goes alone after an argument with Timon who believes leaving means giving up all him and Pumbaa searched for. During Pumbaa's journey to Pride Rock, Timon reunites with Pumbaa and battle the hyenas and save the Pride Lands. Timon and Pumbaa return home with Simba and Timon's meerkat colony to celebrate.
In the television series, he and Timon are once again the main characters, and are shown to travel a lot and had many adventures. These adventures are usually due to the fact that Pumbaa always wants to do the right things all the time. In the series, Pumbaa seems to truly be the brains of the duo while Timon thinks and tells that he is. In the show, it's also shown that Pumbaa is very popular among the jungle and usually gains the chance to live the glamorous life, but gives it up for Timon.
One episode revealed that Pumbaa's last name is Smith. This was likely meant as a joke due to how incredibly common Smith is as a surname.
Role in the series
Pumbaa is an ally to Spongebob and his friends, as the warthog is a member of the Jungle Adventures Crew.