Naughty Bear is the main character of the Naughty Bear series. He is a brown teddy bear who lives on Perfection Island, home to living teddy bears. Naughty Bear is bullied by the other bears repeatedly, and this has caused him to become demented in the brain. After a failed attempt at becoming friends with the other bears, Naughty Bear finally snaps, going on a rampage and killing the other bears who come back to life. The other bears respond by repeatedly trying to kill him, but he manages to defeat them every time. Naughty Bear's favorite food is cake, and when he gets injured, cake will heal him.
Seeking to find acceptance in the other bears eyes, Naughty Bear has made a present and is coming to Daddles' birthday party despite not being invited. He hasn't even arrived at the party when two bears named Chubby and Giggles laugh at his present until he goes home. The unseen Narrator is shocked by the other bears cruelty and tells Naughty Bear to throw his present in the fire and kill Daddles and the other bears. Naughty obeys and after desposing of his present he sneaks out and attacks the helpless bears at the Factory. The bears at the Disco where the birthday is held hear of this and arm themselves, but are all defeated by Naughty Bear and Daddles is killed. Naughty Bear returns home after the rampage.
Naughty Bear is resting in the forest when he happens to overhear an election at the Cabin. He spies on the bears and learns that Chubby, one of the bears that had taunted him in the previous episode, is running for mayor and has promised the bears that if he wins, he will send his ninja bodyguards to eliminate Naughty, earning him the votes of many bears. Enraged, Naughty goes on another rampage and starts killing off the bears until he arrives at the Disco and confronts the gun-weilding Chubby. Naughty kills Chubby and returns to his hut while the ninjas leave, having failed to protect Chubby.
Naughty Bear notices a fluffoul with a camera attached to his head. He investigates and finds out Cozy and the Army Bears have attached cameras to the fluffouls to spy on Naughty to make sure he doesn't cause trouble. An angry Naughty Bear promptly starts destroying the fluffoul cameras and arrives at the Cabin to terminate Cozy, who is heavily guarded by Army Bears. After getting rid of Cozy, Naughty leaves.
During nighttime, Naughty Bear happens to see the wonderful and mythical Unibear, but the Unibear is scared off by the arrival of several bears that have been invited to Nibble's cooking lesson. Disappointed that he wasn't invited, Naughty somberly returns to his hut, only to learn Nibbles has accidently read the Dead Book and has summoned a horde of Zombears. Upset, Naughty fights his way to the Cabin, where a battle between the Zombears and Army Bears is raging on. In the chaos, Naughty Bear (or the Zombears), punish Nibbles and Naughty returns to his hut as the Zombear threat is dealt with.
Naughty Bear learns that Trembles has been promoted to Oil Baron and has returned to Perfection Island. While Naughty Bear watches, Trembles reveals his plan to have his B.E.A.R. bodyguards slay Naughty Bear and then drill for oil at his hut, which the other bears are only too happy about. Furious, Naughty goes on a rampage, killing off many B.E.A.R. bears and tracks Trembles down to the Cabin, where he murders Trembles and then returns to his hut.
Naughty Bear, while playing with a fluffrog, notices a robotic bear, and follows it Fluffy's hideout at the Factory, where he has constructed an army of R0B0-B34R5s and is working on a super-brain, and is in possession of a Zero Point Quantum Grid Resonator that could potentially end the universe. Determined not to let this happen, Naughty Bear fights Fluffy's robotic army and punishes the purple bear, eliminating any threat of destruction.
Naughty Bear, sitting from the top of a roof, watches a friendly bear named Sunbeam star-gazing during nighttime. Sunbeam is friendly to the other bears, except Naughty Bear, upsetting him. A spacecraft starts hovering near the island, and an excited Sunbeam tries to make contact with the aliens. Naughty is somewhat disturbed by this, but his suspicions prove correct when the alien bears land on the island and force Sunbeam to surrender by holding him at gunpoint. Sunbeam then has a mind-control helmet placed on his head, cauing him to follow the aliens command. The aliens then start to invade the island and brainwash the other bears, including ninja bears, zombears, army bears, and R0B0-B34R5s. As the aliens start to take over, Naughty, who wasn't brainwashed, fights the alien menace and manages to gain th upper hand despite being outnumbered and outgunned. Naughty punishes Sunbeam for bringing the aliens on the island and manages to defeat the aliens and force them into retreat. The other bears initially appear grateful for his actions and throw a celebration for him, but Daddles smashes a cake in his face, earning him the ridicule from the other bears, who had tricked him.
Saddened by this, Naughty Bear returns to his hut while the other bears party inside the Cabin. However, Naughty Bear gets his revenge by shooting the Cabin with an RPG, destroying all the bears inside.