When Neptune is in her coma at the beginning of the game, she hopes that she doesn't go crazy and start "collecting rings floating by the ground" or wandering around and "stepping in some ABC gum".
Vert gives us a now-outdated reminder to preorder Hoop: Reach.
The party runs across a lone member of S.R.A.T.S. who suggests you should be a "master of unlocking". The member even looks like Chris Redfield (his Resident Evil 5 incarnation).
The description of the Overlord Momus item says, "If you collect all five, the Overlord will awaken." Overlord Momus, obliterate?
One of the first few lines Neptune has is, "Neptune does what you all don't," which is appropriate since Sega, which Neptune represents, used "Genesis does what Nintendon't" as an advertising line back in the day. What's more, this was a purely American ad campaign; the translators were actively adding to the shout outs, even obscure ones that many kids today likely wouldn't know about.
Neptune, Compa and IF run into a group of "road pugilists" beating up on barrels and used cars, among them a sumo wrestler and a cute Chinese girl with "really monstrous thighs".
The first time Neptune and her friends prepare to go terraporting, she thinks she's supposed to make a long jump across to reach the other landmass, and IF dares her to put on overalls and a red hat.
Horsebirds won't make any sense unless you've played Final Fantasy XIV where they have renamed Chocobos into horsebirds. Compile Heart took it Up to Eleven.
Steins Gate characters Kurisu Makise, Mayuri Shiina, and Itaru "Daru" Hashida make a cameo as part of 5pb's attacks.
Nepgear's dream reenacts the entire sequence of the third episode of Puella Magi Madoka Magica right down to two of the seiyuus (Nippon Ichi being Mami and Uni being Sayaka) and of course includes the head chomp.
Gamindustri's preferred social networking site is Chirper.
When gaining a level, Neptune may occasionally hum the victory tune from Final Fantasy.
5pb provides the voice for a synthesizer, but becomes upset that people are making her sing and dance to rather strange things.
MetalDogoos are hidden in a single group of enemies in LAN Castle. They're worth about 4 times the Experience and twice the Credits as the rest of the fight, and their Metal Jelly sells for another 11111 Credits.
Vert's Military Dress costume adjusts her color scheme in such a way that she looks like Luka.
In a Chirper event focusing on Nisa, Blanc is reminded of a game where the main character is part of a secret Broadway troupe living in New York. The game in question is Sakura Taisen V, which was released by NIS America.
Blanc mentions that she likes ordering books from Blarnes and Foible (Barnes and Noble).
The first time the group meets Linda (a low-level ASIC thug), they mock her "soldier" title and tell her she's nothing more than an "underling" (perhaps even a Mid-Boss?) Just as in Disgaea, Linda's on-screen title changes to reflect this.
Yet another Vocaloid reference is made by Noire's Stone Leek costume by name and description. However design wise it looks closer to being Dees Vanguard than Miku.
There is a quest given by a "UniSound-Alike". She needs you to kill a few Cuberials who tricked her into taking on a curse to make a wish. Another quest is given by a "Small White Animal" who has made so many contracts with young girls that it needs you to go out and get it some more magical contract paper.
In Chapter 7 a new NPC that looks almost exactly like Kyubey in shows up in Planeptune named Rokubei. It wonders why you'd be asking it about a contract and insists that it's just a cat.
When Nepgear is talking with Vert about how she's no longer the main character like she was in the last game, Blanc comes by to inform her that she has Dragonball Syndrome, where the older family member passes the lead role to a younger one only to steal it back and that it can only get worse from there for the younger character.
Noire's Elysdeon returns from the first game. The description now also mentioning that it was built by Landale & Landeel Enterprises.
On the way to Lowee the group comes across a patrol and Neptune suggests that they "go all Roads of Fury on them." And that she gets to be the guy on roller skates.
Plutia's Thunder! and Super Thunder! attacks change to Thunder Blade and Super Thunder Blade in HDD.
When Plutia is about to transform to give Noire her "most popular lecture" in chapter 3, Neptune tells the player to "Press the B Button to stop the evolution" (Well, in the Japanese version, at least.)