The Anime of the Game: One is in preparation. There's also a manga, but only in Japan, and only the first two chapter were scanlated. The rest can be found online, but in Japanese.
Annoying Younger Sibling: In Blanc's case, it's annoying younger siblings. Ram and Rom tend to give her quite a lot of hell.
Ape Shall Never Kill Ape: In the first game during the events on Leanbox where the group agrees to help the Parliament with the Basilicom, IF specifically states the party will not get involved in missions attacking other humans.
A Wizard Did It: Arfoire's overall character design is a witch. If you're wondering, R4 is a program that allows users to play (allegedly) pirated games on the DS for free. The questions that arise are: "How the hell can a person get a physical cartridge into a form that a computer can read with no documentation whatsoever?", and "How can a person create a program for a console that has no documentation and allow it to work with said cartridge, let alone emulate it in it's entirety?"
Bare Your Midriff: 5pb./Lyrica and HDD Vert, who has both midriff and Underboobs. mk2 has HDD Uni, HDD Nepgear, Falcom and Linda/Underling, and Victory has Noire in her regular form and Plutia as Iris Heart.
BFG: The guns that Uni likes to use are considerably larger than she is, and when she activates HDD, her weapon increases to a ludicrous size.
BFS: Neptune has blades such as the Bastard Sword and Claiomh Solais, and Noire has Elysdeon; this is also applicable when they activate HDD, no matter what sword they initially had. Blanc has her variant in giant hammers, and axes when she's White Heart.
Bishoujo Series: Every single important character is a woman and the guys at best get a portrait with a silhouette. And mk2 is no exception except for the three male characters that are the villains.
Lampshaded in one mission where Compa says they can recognize the boy/girl they're going to save because he/she is simply an NPC silhouette.
Bratty Half-Pint: Ram and Rom to Blanc, given that the former two are the latter's younger sisters. Ram is worse though, considering the fact that she antagonizes both Blanc and Nepgear in mk2, even after joining forces with Planeptune's CPU Candidate.
Breaking the Fourth Wall: Many instances can be found throughout the games. Neptune, Compa and IF thank you for playing in the ending of the first game.
Break Meter: It only last about ten seconds in the first game, making animation skipping a must to get the most out of it. It lasts much longer in the second game and they finally found a balance in Victory.
Breast Expansion: Applies in one way or another to all of the goddesses when they power up, but is most noticeable with Neptune and Blanc, the latter because her breasts grow up one letter in cup size, and the former because she goes from flat-chested to generous E-cup breasts by virtue of her true body being much older-looking than her avatar. Plutia from the third game goes through the same change as Neptune.
It's notable that the inverse happens with Uni, prompting Nepgear to ask if she was "stuffing them".
Cool Ship: Neptune has the ability to transform into one for one of her special attacks.
Cosmetic Award: Seems to be mocking the trophy and the achievements systems since doing something will already get you a trophy right off the bat. Start a New Game? You already got your first trophy! Finished the tutorial stage? You get a trophy!
Indeed, except for a few trophies one must actively pursue, the majority of them are earned just playing the game without any extraneous effort.
Taken Up to Eleven in mk2 where before you even have your first fight against CFW Judge, you already get three trophies.
Then they just outright play it for laughs in Victory when Nepgear gets affinities that do nothing while a cutscene happens. Not helped by the fact that a self-aware tutorial pops up while this happens the first time.
Cute Bruiser: Practically all playable characters. Take pity in those who are foolish enough to underestimate them just because of their looks, especially Compa with that giant syringe.
Damn You, Muscle Memory: If you played Mk2 first, the Square is for Symbol Attack, and Circle is for Searching. If you then play V, you'll find out that Square is for searching items, X is for symbol attack, and Circle is for jumping (which wasn't present in Mk2).
Date Crêpe: In one of the bonus artworks designed by the company, Noire and Neptune do this, as well as Blanc and Vert.
In the second game, you can edit your character's outfits and the goddesses' processor units for some stat adjustments.
This is continued in the third game, however instead of just being able to edit Nepgear's canvas, you can edit all the CPU's. There is also a disc system that lets you add passive abilities to a character.
Dub Name Change: Magiquone and Nippon Ichi, who are named Arfoire and Nisa, respectively. Magiquone is a play on Magicon, the name of a flash cart sold in Japan, whereas in America, the most popular flash cart is the R4 (so they changed the name of the boss so people would get the anti-piracy overtones). NISA is an acronym for Nippon Ichi's American branch.
Neptune's nickname for IF goes from Ai(I)-chan to Iffy.
In the second game, the villains that are named [Blank] the Hard are renamed as CFW [Blank]. In this case, CFW stands for Criminal of the Free World, and is meant to make people think of Custom Firmware.
Pururut's name was changed to Plutia, possibly to clash well with Neptune's name. The original name could have been thought to be a pun on the colour purple, but listening to the dialogue in game, it's pronounced "Pururuto", meaning the Pluto pun was there to begin with.
Duel Boss: Neptune vs. Arfoire later in the first game, as well as when you try to recruit the other goddesses.
Emoticon: Histoire seems to really like using this in her fairy mode.
Fanservice: Both games have this from the start. The first one starts with Compa wrapping bandages around Neptune's naked body because... because. mk2, overall the raunchier, starts with the CPUs getting ravaged by cable tentacles because... because. Of course, both games have buttloads of non-sexual fanservice as they are, after all, about the console wars.
Fiery Redhead: RED, Falcom, and Cave, but since her personality is cool as ice, Cave is a subversion.
Gondor Calls for Aid: In the original Neptune wants the other goddesses to help, but they don't want to. She has to beat the crap out of them again to make them help.
The Gods Must Be Lazy: The goddesses spend more time on their personal affairs and bonking heads than actually running their lands. Vert averts this later in the first game by going out and actively fighting monsters.
Gods Need Prayer Badly: Goddesses gain power with belief. Arfoire uses this to gain power again by spreading false overlord rumors and harvesting their fear in the first game. In the second game, ASIC buys support by giving out modchips.
This is actually a gameplay mechanic in the form of shares. More shares translates to more faith and power in a goddess. A certain amount is needed in order to recruit the goddess of each land. In the case of mk2, shares allow you to recruit the CPUs and affect the ending.
Gratuitous French: The CPUs that aren't Neptune have French names (Noire, Vert, Blanc).
Gratuitous German: Quite a bit, actually, mostly with Blanc whose attacks have garbled names such as "Todlichschlag" (if they were going for "deadly strike", it would have to be "tödlicher Schlag"), but other characters also get in on it, like Neptune's and Nepgear's Combination Attack in the reboot, "Violet Schwestern" ("violet sisters" or "purple sisters" would be "Violette Schwestern").
Guide Dang It: It's an Idea Factory game, which means an incredibly obscure undocumented system must be used to reach the Golden Ending.
The first game fails to mention that Neptune dying in battle has a hidden penalty and that if she dies too many times it can permanently lock you out of events — including the events to reach said ending!
Have You Seen My God?: The first game sees Planeptune's Basilicom understandably upset when Purple Heart doesn't show up when the goddesses start arriving. And in the Golden Ending, all four goddesses call it quits and leave Historie to create a new goddess to rule in their place.
Improbable Weapon User: The worst offender has to be Compa who uses a syringe that shoots bullets! This is even Lampshaded by IF at one point in the first game, and Nepgear in the second. 5pb. isn't off the hook due to her weapon of choice being a guitar. She'll either whack enemies with it, or kill them softly by playing some music.
What's this? The third installment has finally added a human male that isn't a silhouette? Oh wait, he's a villain.
Informed Equipment: Semi-averted. The rings and bracelets merely give a description of what the item would look like and change a character's stats, but the hats/hair accessories and dresses actually show up on the character's person and are most likely there for the sake of customization since those items tend to not affect stats very significantly.
Instrument of Murder: 5pb uses a guitar as her weapon. If she uses a special attack, she will play it. But in normal hits, she will smack the target with it.
Jail Bait: Linda calls Nepgear's group "jailbait tramps" in mk2.
Jerkass: Ganache. He assigns the task of finding a rare ore to the party, and confines them in an abandoned building set to explode. Afterwards it turns out that was only a diversion, as stated by IF when Chian's factory is being sieged by Avenir robots.
Large Ham: Nisa, the self-proclaimed justice loving super heroine of Gamindustri. Chika as well, especially when vocalizing her... "admiration" for her "sister" Vert. She even comes off as a Large Ham when first introduced to the player when Nepgear and co. find her in Underverse faking death.
Lazy Backup: If your three frontline characters die, it's a game over with no explanation whatsoever when you have eight (ten if you include 5pb and RED) characters in your party. The second game also has this problem except you have fifteen characters to choose from and yet when the four on the frontlines die, it's a game over.
The above example of the second game gets even worse when you remember you can equip characters to each other to produce secondary effects. It would make sense that when the character dies, the equipped character takes over. Sadly, this isn't the case.
Neptune: What's up? A favor? Ask me anything! Oh, but no touching. Got it? No touching!
Jade: Don't treat me like a pervert when I'm about to die.
Motive Decay: By the end of the game, Arfoire goes from trying to remake the world to simply destroying it. It's explained that her fear-derived power basically eroded away her mental stability to cause this.
Never Trust a Trailer: The first game advertises that you get to play as the goddesses in the middle part (or at the very least, early-middle part) of the game. You only get to play with them in the final dungeon and possibly post-game.
New Game Plus: Present in all games, although the first game gives you the option of playing in an End Game Plus, which is convenient for getting all of the endings.
Nobody Poops: Averted in one instance where Nep-Nep nearly misses out on Nisa's introduction by spending most of the preceding battle on the toilet.
Averted in another cutscene where Neppermint admits to being a little too excited about a visitor.
Face a foe who's a significant number of levels above you and Nep-Nep might start the fight by requesting a change of underwear.
No Budget: The first game ran out of money and was mostly unfinished. The second and third games were given a higher budget and received a warmer reception.
Glimpsed when Neptune bends over while using her hammer skill.
The status of your characters covers it up until you press X to exit the battle, but in the original game Compa falls over after you win. The camera angle is situated in front of her so that you can see her undies for a brief second after the status leaves the screen. It's only for a fraction of a second.
Subverted in Victory, where one of the character challenges lead you to believe that you have to view the character's underwear where you really just have to jump.
Party in My Pocket: Well, obviously! Then again, you can switch out the on-screen avatar, which is actually important in the first game because different characters have different functions on the map screen. For instance, Neptune pulls out a hammer to smash obstacles, Compa rings a bell to attract monsters, and IF uses her search mode to uncover invisible chests.
Power Floats: Whenever Neptune, Blanc, Vert, and Noire (or their sisters) transform to their respective goddess forms, they always float in the air.
Plot Tunnel: On the few occasions where Neptune leaves the party in the original, you cannot leave that landmass until she returns. Justified in that she's the one who registered for permission to travel to begin with, and you'd need her for cutscenes in other landmasses anyway.
Rainbow Pimp Gear: Generally averted with the outfits and accessories you normally get for the characters, but you make some truly outrageous processor combinations for the goddesses.
Rank Inflation: Timed dungeons. The faster you finish the dungeon via beating the boss, finding the secret treasure, or getting lucky with item drops from random encounters, the better your rank will be. This always often leads to a Bragging Rights Reward when you beat the record times of other players.
Rule 34: For an Idea Factory game, this is perhaps the most popular choice as Cross Edge and Record Of Agarest War, despite being much more ecchi, had little to no Rule 34. For example, there are official NSFW dakimakura covers of Noire. That's all we need to say.
Rule of Three: Planeptune has had three known Goddesses. In chronological order, it would appear to be Caelus, a former Goddess in the Mk2 timeline, Plutia, a goddess from the past in an alternate timeline, and Neptune herself.
Saving the World: Both figuratively and literally (figuratively being Histoire who is the "Tome of the World" and literally being "kill Arfoire and all of piracy").
Scripted Battle: The first "battle" in the series is Purple Heart vs. the three other CPUs.
Gets parodied at the beginning of Victory. It's really a video game.
Self-Deprecation: The weakest and least versatile characters in the first game are IF and Compa. They don't even get any sort of Limit Break, something even the DLC characters were given.
So Long, and Thanks for All the Gear: Uni notwithstanding, completely averted. Most characters who join you never have to leave for any reason, aside from a handful of scenarios which have them leave for one dungeon. In the first game, however, the equipment will reset on the character when they return, forcing you to re-equip, but this is a minor annoyance at worst.
Stripperific: When in HDD, all of the goddesses. All of them. Of significant note are Vert and Uni. CFW Magic ups the ante.
Chika Hakozaki wears a dress that isn't as revealing, but still manages to show a significant amount of skin.
In Neptunia Victory, HDD Noire reveals slightly more; HDD Neptune doesn't change much, though the abdomen part of her outfit is mostly transparent now. Noire's regular outfit shows off midriff and Zettai Ryouiki compared to the cleavage-sporting dress seen in the first two games.
And speaking of midriff, there's also 5pb.
Heck, this can be any of the playable characters with DLC swimsuit outfits.
Strongly Worded Letter: Played straight in the original when Neptune and her friends send a series of threatening letters as a tactic to lure out Arfoire, Overlord Momus' messenger and separate her from a group of extremists she's leading. The plan actually works, but for a reason none of them expected - because Neptune misspelled Momus' name as "Overlord Moron".
Super Mode: Hard Drive Divinity. In the original game, it lasts until the battle ends or the user is incapacitated, while in mk2, HDD lasts as long as the user still has Skill Points to spare, unless of course, the user is incapacitated.
Take That: Unsurprisingly, there are a few zingers in here, but it's mostly gentle poking instead of straight-up insulting and no company really gets it worse than the others.
Thanking The Player: In both endings of the original, the main trio directly thanks you for getting them through the game.
The Dev Team Thinks of Everything: If you change Neptune's clothing and use her hammer skill in the field you can see that they took the time to change the color of her panties to match her stockings.
Symbolic Rape: Croire forcing Rei to swallow the entire black, evil mass can count as this, especially considering the term "black mass" and Croire telling Rei to open her mouth wider so she can force it in easier.
Transformation Sequence: Upon activation of Hard Drive Divinity, the user switches into a Stripperific bodysuit, her hair grows (or changes to drill hair in Uni's case), her eyes glow and sport power switch shaped pupils, and her weapon will increase in size or at least change how it looks to fit the appearance of the user; in Neptune's case, her voice is also changed. The Transformation Sequence is very Sailor Moon-esque in the first game and rather lengthy at that, but can fortunately be skipped with the press of a button. Arfoire likewise gets a transformation in the first game as well; into a colossal and powerful dragon, that is.
Video Game Perversity Potential: The first game allows players to use pictures stored in their PlayStation 3 units for "R/W disc" special attacks — even pornographic ones. The second game allows Nepgear's CPU outfit to be customized via the Costume Canvas system, and "nude mods" have been made. The third game extends the Costume Canvas system to the other CPUs and the CPU Candidates, allowing even more perverted potential. Have fun.
You Gotta Have Blue Hair: Let's see, we've got: purple, blonde, green, light blue, black, white, brown, pink, blue, and red. And this is just from the main cast.
Yuri Genre: The first and third game fall squarely into this due to Red and Iris Heart, in addition to all the Homoerotic Subtext and Ship Teasing between the various characters. mk2 comes close, but never really goes much further than the subtext, teasing, and one offhand comment in Uni's character info quotes.
Surprisingly, despite all the subtext and official romantic interests, the majority of the characters seem to have at least some interest in men, though who and how much varies from one continuity to the next. For example, in Victory during a comedy scene where Vert is eyeing Nepgear oddly (Because she is deeming her fit to be her sister), the party are wondering if she is "choosing which team to play for" and show surprise that she might be into girls given their earlier introduction to her hobbies.