- "He is hungry. Hungry in the Dark."
- —Peter Michael "Little Pete" Ellison Hunger
Peter is a four year old boy. He has the same features as his sister Astrid- the blue eyes and blonde hair. He is found holding onto his game console and playing on it even when it is broken because of his game with the Darkness. His face is usually blank since he is said to be hard to read, and because he is autistic.
Peter looks like a normal four-year-old but does not act like it. He does not have much personality throughout the book until he is free from his body. He doesn't pay attention to his surroundings since he is playing on his game. He says the surroundings and his sisters hair "scream", showing that colours are too bright for him. He rarely speaks or responds to anyone or anything. In Gone, Astrid "The Genius" Ellison hits him with her concrete block to distract him from his game so he can make the cement disappear. This shows that when distracted from his game he will pay attention to what is around him and get rid of what is annoying him.
After the creation of the FAYZ; Astrid, Sam Temple, Quinn Gaither and Edilio Escobar go on a mission to find Pete. Astrid explains to them that Pete is her little brother who is autistic, and doesn't respond to others. She suggests to check her home and the power plant, where their father works at.
Upon arriving at the power plant, they find Pete, playing on his handheld game.
One of his powers is discovered when Sam trips over an object, causing a huge commotion, thus scaring Pete and choking Sam without force.
When arriving home, Howard Bassem taunts Pete by calling him "Petard". Pete is bullied by Zil Sperry, Howard Bassem and Panda when they throw a rock at him, calling him "Petard". As other events happen in Perdido Beach, Pete is very unaware and is focused on his game.
After finding a security tape recording of the power plant, minutes before the FAYZ was created, it is revealed that Pete was the cause of the FAYZ.
Another of Pete's power is discovered when Drake "Whip Hand" Merwin bullies Astrid. After being forced to call Pete "retarded", Astrid is slapped, and Pete teleports them to their home.
In Hunger Pete's dreams come to life as real beings. He is also in contact with the Darkness, who thinks of him as “Nemesis” - “Nemesis with infinite power held only in check by the twists and turns, the blind alleys and sudden high walls inside his own damaged brain”. He plays "games" with the Darkness who uses these "games" to make Pete do what he wants. Pete goes to the Darkness in his head to escape the overly bright real world. It is important to note that Little Pete caused the FAYZ in one of his panics.
At the end of the Battle on the Clifftop, Pete is with Astrid. When his Game Boy is destroyed, he causes the wall to disappear, exposing what was behind the wall. Astrid recalls seeing a motel, news vans, a fence, and lots of people. Pete makes the wall reappear and is oblivious to what had happened.
In Plague, Little Pete is severely dumb with a cold. Drake is looking for Little Pete. Astrid is thinking about killing him off to see if the wall comes down. Little Pete's powers are out of whack. He made an illusion of their mother appear, and made it start raining above their house. He also destroyed the upper 1/2 of his house while Astrid was in the backyard. After that little incident, Astrid, Little Pete and Charles "Orc" Merriman go to Coates Academy, where Drake finds them in order to take 'Nemesis' (which is what the Gaiaphage calls Pete) to the Gaiaphage for either his demolition or for the Gaiaphage to take over. When Drake finally shows up, he turns into Brittney Donegal, who has a conversation with Astrid. Then the bugs show up, Orc fights them, Computer Jack shows up and Brittney turns back into Drake. Drake and Jack then have a little argument, because Jack is there to kill Little Pete, and Drake doesn't want that. Just as Drake is slowly getting the upper hand, Astrid chucks Little Pete out the window at the bugs. Little Pete doesn't even hit the ground. The bugs disappear as Little Pete floats down. Then he just coughs once and disappears, ending his life with autism. He somehow remains alive, even though his body was gone.
In Fear, Little Pete is not physically alive anymore. Astrid killed Little Pete, because giant bugs were attacking the town and the only way Astrid could get rid of them was to kill Little Pete. But because Little Pete is a 7 bar, or maybe even higher, he turns into a kind of spirit. He is playing a sort of game and everyone in the FAYZ is an avatar. When he touches them they die though, and Little Pete ends up killing 1 person and violently harming Taylor. He then reaches out to Bradley "Cigar" and is able to talk to him (but causes Cigar to go insane) and contacts Astrid through Cigar.
In Light, Little Pete is still a spirit. Gaia Soren-Ladris is afraid that Little Pete will find a body to fight her, so she makes it her goal to kill everyone in the FAYZ. Gaia was constantly urging Little Pete to just "disappear" and die, which would cause the FAYZ barrier to come down. In an attempt to make a person fall through the FAYZ wall, Gaia somehow "hits" Little Pete. This infuriates Little Pete and makes it his goal to fight Gaia. In the end, Little Pete (in Caine's body) fights Gaia in an epic finale. Gaia attacks Little Pete with Sam's killing light. In a counterattack, Little Pete attacks her with "a light that came from all directions." They ended up killing each other, ending the FAYZ with Little Pete's death, and the mutations with the Gaiaphage's death.
- Astrid "The Genius" Ellison: Astrid is not only Pete's older sister but his "killer". Pete doesn't seem to like his sister since he describes her as beautiful, but yet she has blue painful eyes. Astrid helps him out with exercises for autistic kids. Astrid volunteers in Light, for Pete to take over her body, but he says he doesn't trust her.
- Howard Bassem: In Gone, Howard is a bully to Pete, calling him "Petard". After Gone, he doesn't bully Pete.
- Charles "Orc" Merriman: In Plague, Orc saves Pete from the remnants of the Human Crew and defends Astrid from Drake in Coates in the end of Plague. He thinks of Astrid as his only real friend.
- Gaiaphage: The Darkness feeds on nuclear energy and when it comes into contact with Freaks it co-opts their power, particularly that of Lana Arwen "Healer" Lazar, Caine Soren, Little Pete (or Nemesis, as the Gaiaphage calls him) and Drake. It uses Lana's power to create Drake's whip-hand, Little Pete's to create Nerezza and to resurrect Brittney Donegal. The Gaiaphage is locked in battle for supremacy over the FAYZ with Pete, the autistic five-year-old. Its name revealed to mean "World Eater" in Plague. It is a strange organism, possibly known to have made the FAYZ built of Alien DNA, Human DNA, and raw radiation. In Fear, the Gaiaphage is reborn in Diana Ladris's baby, and it is revealed by Little Pete that the barrier is made from the Gaiaphage, and that the main reason the barrier was going dark was because of the Gaiaphage getting weaker. In Light, when LP takes over Caine's body, LP and Gaia Soren-Ladris go against each other for the ultimate final battle. Both of them die at the same time and the FAYZ wall comes down.
- Taylor: In Fear, Pete accidentally mutates her after touching her avatar, changing her body, turning her skin gold and causing her to teleport into things. In Light, he tries fixing Taylor by adding her hair and changing her eyes. He also says he sorry for what happened to her, he did not mean to hurt her, he was too weak.
- Bradley "Cigar": After Cigar's punishment to a crime he committed, Lana tries to grow new eyes for Cigar but fails and Cigar ends up with another type of vision where he as the ability to see Pete. Cigar helps Astrid communicate with Little Pete for the first time, at the expense of his sanity.