All There in the Manual: This page is pretty much the main "manual" for some of the characters' backstories. There are also a few other works made by the RPers showing things such as What If? scenarios and characters not seen in the RP proper. Said scenarios may also count as Recursive Fanfiction.
Arbitrary Skepticism: Averted. There's no reason why they shouldn't believe in the things they encounter.
Chie still finds the non-Persona related things around her hard to believe, though.
Rho includes some Vietnamese in her dialog as well.
In an odd case, Taichi and Sayaka had a conversation in binary and base64. It's probable that all the parties involved threw their text into a translator, though. Haruka and Ryuuta did just that to see what was going on.
Birthday Episodes: Characters usually take the time to have some sort of celebration event for the birthday person.
Color-Coded for Your Convenience: The Yuuhi wear black and red. The Asahi wear blue and white. The cheer girls are opposite this. The Yuuhi cheer girls wear blue. The Asahi girls wear red.
Commuting On A Bus: Some characters tend to disappear for awhile, return, then disappear again.
The fact that most of the role players have pretty busy lives is the main contributing factor.
Competence Zone: Averted. Age doesn't make a difference here, even when not in the twenties age range.
Occasionally played straight or inverted.
Continuity Drift: Due to players' different perspectives on the games as well as the continual introduction of outside fandoms.
Continuity Nod: Characters sometimes reference the events that happened in their games. They also refer back to previous FS events including the trips taken during 2011.
Remember When You Saved The Sun From Dying? The sun-saving incident gets mentioned especially often. Other examples involve the zombie infestation of Wonderland, Taichi's dimension-hopping, and the Rhombulan invasion.
Crapsaccharine World: Think about it. Almost everyone has some sort of troubled past or family issue, one character is basically a bad day away from trying to kill everyone and the one thing preventing him from doing so is gone now, the resident cute boys are traumatized from having to fight their friends, and the world has almost been destroyed/taken over nine times *
Three times from the main series, once from Cave Story, and the other five are from the Persona series.
Crossover Shipping: Shipping can get pretty interesting because of all the different series involved.
Department of Redundancy Department: The name of the Asahi's boat. The name of their boat is Asahi Sunrise III, and Asahi means 'sunrise'. So...basically the name of their sailing vessel is "Sunrise Sunrise III".
Let's Just Be Friends: Occurred with Sayaka and Momotaro with the pair including this phrase word for word. However, it's somewhat averted as they still maintained their friendship afterwards with not much trouble.
Take That: Most of the comments Trisil makes about the characters. That's right. A Take That about the RP's characters from one of the RP characters.
Talking to Himself: This can happen whenever two characters that're controlled by the same RP-er interact. Which is more often than you think, since there are only about 7 of us around.
Theme Song Power Up: Invoked during the Halloween Episode, when Reika and Sayaka had a duel while the Leitmotif of their cosplayed characters was playing. Reika had Mars and Sayaka had Purity. It should be noted that Taichi was the one who started the theme-playing in the first place.
The Three Faces of Eve: The innocent Honoka as the child, the often worried Reika as the wife, and Sayaka who loves sexual things as the seductress.
Those Two Guys: Two sets of them, actually. Morris and Derek. Sugita and Moriyama.
Toilet Humor: Happens few times, especially since it's implied that Nobody Poops is averted when the situation calls for it.
Twerp Sweating: Kai had a few "discussions" with Momotaro back when the peach boy was dating Sayaka.
Undead Tax Exemption: Averted. Momotaro had to go through a formal adoption process when he moved to Yuuhi. Taichi also mentions that he had some problems at first explaining his rather long absence, especially with regards to marriage papers.