According to the local folklore of southwest England, pixies are small mischievous creatures that inhabit the countryside and woodlands that like to play pranks on humans. Depending on the tale told, pixies can vary in size from tiny enough to fit in the palm of a human's hand to the size of a small child, although they are always a good deal below the size of an average human. They can be portrayed with or without wings, and over the years have taken on many traits usually associated with fairies, often leading to the common misconception that they are one and the same.
Pixies are sometimes said to be born in much the same way as humans, however some tales tell that they are humans transformed through misdeeds or magic. They play pranks on humans such as stealing their belongings, throwing things or calling out their names. They may also steal horses during the night and return them by the morning with tangled manes. While pixies usually don't cause any real harm, it is said that if someone follows the voices of pixies, they will never return.
During the puzzle set up in Yoyogi Park, an old saying from Dartmoor; Pixie Led is played out. It was said that travelers that got lost on the moors were being led astray and turned around by the spells of mischievous pixies. In a similar manner, the pixies of Yoyogi Park lead the Demi-fiend astray by teleporting him to various locations if he passes below them.
The first demon you get in Nocturne is a Pixie, who wants to get out of the hospital and go to Yoyogi Park. She'll help you out in getting the card needed to get out. After you arrive at one end of Yoyogi Park, she'll try to part ways with you, but if you tell her you need her, she'll stay with you. For Nocturne Maniax, if you take Pixie (or one of her 'descendants') to a certain area of the Fifth Kalpa, she'll turn into a level 80 "super" Pixie.
Pixie can evolve into High Pixie through leveling up, and High Pixie into Queen Mab through the same method.
Shin Megami Tensei IMAGINE
"Fairies of English legend. They are also called Piskies and Puggsies. Pixies are sometimes said to be the elements of unbaptized children, or souls that have left their bodies. They are small enough to fit into the palm of your hand, but can grow bigger or smaller. Pixies live in groups. They love to dance and can be found dancing in a circle nearly every night. So-called "fairy rings" are said to mark the group where they hold their dances."
—Shin Megami Tensei IMAGINE Compendium
One of the early storyline quests requires players to contract a Pixie variant in Suginami on Snakeman's request. A slight shift to a player's alignment is tied to whether or not they allow Snakeman to take the Pixie entirely to use to create salves or relinquish only the necessary wing fragments. Pixie can be found as an enemy within multiple hacked instances and as support to Titania and Oberon in their boss room. Pixie NPCs regularly appear as part of quests whether being the quest-giver looking to learn about other demons, a target of revenge for Cathedral researchers, or as the target of an Incubus' desire in the Deranged Scheme questline. A Pixie is also an essential part of the Dewdrops from a Flower quest chain where she offers part of her wing to aid in the creation of an antidote for Titania. Players can interact with a Pixie NPC in Club Hourai as part of the Interaction Time System. A pixie appears as support for Demi-fiend when he acts as an event boss.
Players can equip Pixie wings and Pixie is one of the mountable demons and bazaar tending demons within game.
Shin Megami Tensei: Strange Journey
"A small faerie found in southwest Britain. It is cheerful and likes to play pranks. Their physical appearance changes from region to region, but their personality is always cheerful and prank-loving. One common prank they pull is to cause humans to travel in circles. However, they also help farmers and are generally considered good faeries"
—Shin Megami Tensei: Strange Journey Compendium
Pixie appears as the demon recruitment tutorial as well as the first recruitable demon. It appears as a preset encounter in Sector Antlia, not far from the entrance. It first appears as an unknown entity unreadable to the Demonica's systems, but immediately makes itself visible to impart the tutorial. Afterwards, it's possible to recruit the Pixie.
Pixie will also issue the first possible EX Mission, The Injured Little Fairy, in which Pixie requests a Bead, which can be obtained as the spoils of the battle against Morax. Accomplishing this mission is rewarded with a Pixie Knife, a melee weapon that can inflict charm. Later, the same Pixie will evolve to High Pixie and begin issuing requests to bring Fairy demons to her so she can create a land for Fairies. Despite this detail, the player cannot obtain a High Pixie through direct evolution and must instead use Special Fusion.
There is a special staff password that will unlock a Pixie with special starting stats. The resulting Pixie will only be Lv.1, but will have a magic stat of 10 and a luck stat of 99 along with knowing the skills Megidolaon and Mediarahan. The password is Madoka Ueno.
Devil Summoner: Soul Hackers
"A small faerie found in southwest Britain. It is cheerful and likes to play pranks. Their appearance changes from region to region, but their personality is constant. One common prank is to cause humans to travel in circles. They also help farmers, however, and are generally considered good faeries."
—Soul Hackers 3DS Compendium
Pixie is one of the lowest level demons, and along with Knocker will offer a tutorial on demon negotiations at the Algon NS Building. In addition, it is possible to obtain a special Pixie from a Pet Shop trade that can cast Megidolaon.
In the 3DS remake, a variant Pixie is available from Nemechi, one of the first available from the start. She costs 100 D-Souls and uses her artwork from the first Devil Summoner installment. This Pixie is slightly more powerful, specializing in electrical magic instead of force, and is the earliest demon with Recarm.
Megami Ibunroku Persona
Pixie is the lowest leveled Persona of the Lovers Arcana, on par with the starting Personas and can only be fused using low level Spell Cards or with a gem that lowers the rank of the Lovers Arcana (example: Yoma Agathion + Spirit Poltergeist + Aquamarine). Despite the low stats when first fused, Pixie receives a noticeable increase in its Magic Attack and Luck stats as it ranks up, with a Magic Attack of 164 and a Luck stat of 94 at Max Rank (possibly more if the result of a beneficial fusion combination).
The Persona itself also differs from its demon counterpart, wearing the traditional leotard in a red color, along with matching long boots and short gloves. Returning a Max Rank Pixie in the Velvet Room yields a Luck Incense.
Persona 2: Innocent Sin
"A mischievous English fairy who dances in forests at night."
—Persona 2: Innocent Sin Profile
Unique to Pixie, Luck stat will receive massive surges over rank ups. At rank 8 her Luck stat will be maximized at 99.
Persona 3
"In English myth, they are fairies of the forest that love to play tricks on people. They can also be hard workers when necessary."
—Persona 3 Compendium
The "super Pixie" is alluded to during the optional fight with Elizabeth. If any of Elizabeth's rules are broken, she summons a powered-up Pixie which is immune to every attack, along with knowing Diarahan and a powered-up Megidolaon.
DemiKids Light & Dark
"Fairy-like demon who is quick to lend assistance in return for a glass of milk."
A Pixie comes to aid the Devil Children when they headed into a poisonous swamp, being able to fly over it and cure them of poison. He later warns them inside the Imperium base that it will soon be destroyed and that they have to escape.
Devil Survivor 2
"A small faerie found in southwest Britain. It is cheerful and likes to play pranks. Their appearance changes from region to region, but their personality is constant. One common prank is to cause humans to travel in circles. They also help farmers, however, and are generally considered good faeries."
—Devil Survivor 2 Compendium
Devil Survivor 2: The Animation
Pixie is the second demon summoned from Io's phone. After Daichi futilely drives the truck in an attempt to damage Dubhe, Io summons a Pixie which has managed to catch and haul Daichi mid-air to safety. It was never seen again (bar small appearances on cell phone screens), and seems to have replaced with Lugh in Io's demon roster after Io's ordeal involving said demon.
Pixie as she appears in the Devil Survivor manga adaptation
Pixie as she appears in Devil Survivor 2
Pixie as she appears in the Devil Survivor 2 manga adaptation
Pixie in Devil Survivor 2 The Animation
Pixie as she appears in Shin Megami Tensei Gaiten Hato no Senki
Pixie as she appears in Shin Megami Tensei: Tokyo Revelation
Trivia
She is typically a friendly, low level demon with Dia that becomes one of the player's first demons. However, this is somewhat subverted in several games, where the player may encounter a massively more powerful version of Pixie as either an ally (as "Super Pixie" in Shin Megami Tensei III: Nocturne) or enemy (as one of Elizabeth's Personas in Persona 3).