The Persona games are known for having expansive stories with a huge roster of characters, but one of the things that set the games apart is that they are almost entirely unrelated to each other. Each game features a separate protagonist, albeit under some familiar circumstances, and the variety of characters around the protagonist changes almost entirely with each new game.
That being said, there are still some similarities between games, and some characters do reappear in later entries. Whether they come back as an Easter egg referencing a previous entry or are consistently important to the story, there are some excellent recurring characters throughout the Persona franchise.
5 Philemon
While player characters and those in their parties don’t recur throughout the Persona franchise, the overarching beings from higher and alternate dimensions sometimes do. For instance, Philemon is a being who lives in the realm of the collective unconscious. He is an ally to the party during his appearances, particularly in both Persona 2 games.
Despite being a neutral observer incapable of actions that could help the party more directly, Philemon has always tried to provide help indirectly wherever possible. He usually does this by bestowing personas on people at every opportunity. He often appears as a man with a butterfly-related mask on, and much of his involvement in the series occurs due to the experiment he has ongoing with his rival Nyarlathotep.
4 Nyarlathotep
The rival of Philemon, Nyarlathotep believes that humanity is destined for destruction, while Philemon is sure that humans can become higher enlightened beings. Nyarlathotep tips the scales in his own favor by placing the curse on Sumaru City in Persona 2: Innocent Sin. He is a shapeshifter that regularly appears in the real world in various forms and doesn’t observe the rules of neutrality that Philemon rigorously maintains.
While this villainous presence, known as the Crawling Chaos, primarily appears in the two different Persona 2 games, he was also named later as the entity behind the puppeteer in the first Persona. This gives him a much more overarching, sinister presence throughout the series as a whole. He even manifested as Adolf Hitler once, proving beyond all doubt he truly is as evil as he can be.
3 The Reaper
It is difficult to have bosses recur within the Persona series. The most significant bosses in each game are usually linked to the characters within the game itself, and these change entirely with each new game. However, there is one character that significantly appears in various capacities as a boss-level character, a creature that is essentially the Persona franchise personification of death.
In games like Persona 3 and Persona 5, The Reaper will appear in a certain area if a player stays for too long on one floor, making for an intriguing time challenge. He can also be found in Persona 4, but only on the second playthrough of the game in Magatsu Inaba/Mandala. The Reaper also makes appearances in Persona Q2, Persona Q: Shadow of the Labyrinth, and Persona 5: Strikers, where he is the secret final boss of the game unlocked only after winning the game and every boss rematch possible. No other character that can be fought has appeared nearly as many times as The Reaper through the Persona franchise.
2 Nyx
This is the only character who reappears in the Persona franchise but may not actually be the same both times. Nyx appears in the first Persona game under the name Night Queen and haunts the mask. Appearing on the B-Path, Nyx freezes the school and turns it into a dungeon with three towers based on Nyx’s children. After merging with Maki and Kandori to form Queen Asura, Nyx is finally defeated and disbands.
However, another Nyx appears in Persona 3. This character is an Eldritch Abomination and is known as the creature who brought the concepts of night and death to the world in the beginning. This character plays a huge part in the game, but it has still never been completely confirmed whether the Nyx characters from Persona and Persona 3 are actually linked or not. Either way, Nyx is a name that will go down in the history of the franchise for the involvement of characters named this in both.
1 Igor
Despite his intimidating appearance, Igor is a hugely important character who has helped the protagonists in each Persona game since the departure of Philemon. A servant of this being, Igor runs the Velvet Room. Not much is known about the Velvet Room or Igor himself except that he can bestow personas onto players and gives advice through the game in the form of scenes that take place in various locations, all of which are considered the Velvet Room.
Igor appears in Persona 3, 4 & 5, and originally used a phone made of bones to call personas to the player. More recently he uses tarot cards to do so. The Velvet Room is known as a place between consciousness and sub-consciousness and has provided players with the opportunity to manage their personas during the game. In Persona 2, The Velvet Room and Igor were a room with a piano and microphone. In Persona 3, it was an endlessly ascending elevator, and in Persona 4 it appeared with Igor in a limo. In Persona 5it was a prison, putting the protagonist in a jail cell. The Velvet Room changes by how the protagonist views this space and their own journey, and Igor changes in how he acts toward the protagonist in each game as a result.