Natsumi: Alright, let's get this over with. Who and what are you? Keroro: Uh, I'm Keroro. I'm the house inspector. Good house. Fuyuki: You look more like a house maid. Natsumi: Don't engage it in conversation! Fuyuki: It's a talking frog! Keroro: That's "Mister Sexy" to you! Oh...
Sgt Frog Abridged is an Abridged Series of Sgt Frog started by Mugiwara Yoshi, currently headed by ThornBrain, and made by TheMidnightFrogs. The series takes the characters' quirks and cranks them Up to Eleven (several characters' Jerk Ass tendencies being taken to absurd levels, Keroro creating even more ridiculous schemes to take over Earth, Dororo getting mentally abused throughout his life, etc.), but nevertheless, the premise of the series is the same of the original, (at least until Continuity Creep set in at the end of Season 1). The writing, however, focuses more on absurdity, surrealism and one-liners than the original's referential humor. Viewers have noted that SFA is considerably different from Sgt Frog.The series is known for being a popular and well-received parody of a comedy, something that numerous people found to be a bad idea before they saw SFA. Its fans include a mix of fellow abridgers, Sgt Frog fans, and people who otherwise don't care for Abridged Series or Sgt Frog. It has numerousarticles maintained by ThornBrain on the team's website, including all of the episodes, side-projects and one-shots, and most of the cast and crew.The first three episodes of the series were remade in the interim between Seasons 1 and 2. Series creator Yoshi stepped down as writer after Episode 16, giving creative control to Thorn. The series ended November 2012, but a revival and a third season was announced on February 14, 2013, starting with a revival special, Sgt Frog Abridged: Reset.The series has a Spin-Off/Sequel audio series, Ask GiroDoro SFA, and it is confirmed to be in the same universe asAudio Logs Of Dr Squid. It is also a sister series to Thorn and BigTUnit1's Jetters Abridged, though they remain mum on if they share a universe. Tropes related to TheMidnightFrogs themselves go on their page.
The series provides examples of:
Aborted Arc: Giroro's crush on Natsumi. Its last appearance was in Episode 10 before Giroro turned his affections toward Dororo, though this was foreshadowed a few times. The sudden drop finally gets addressed in Episode 18: the emotional stress of courting Natsumi to no avail made Giroro lose interest. Presumably he turned his attention to Dororo shortly after.
Giroro: "You know what? Forget it. I like cock now."
Abridged Series: Not the first abridging of Sgt Frog, but by far the most successful. It became one of the few abridged series to have a conclusive ending on November 2012. For a time.
Keroro often speaks Spanish or embodies various Hispanic stereotypes due to his voice actor Yoshi being Dominican.
In Episode 2, Aki mentions that the guy who removed the ghost from the basement was "some guy from Florida", a reference to Kululu's voice actor, Jpace92, a then-resident of Florida.
All of Tamama's invasion plans in Episode 9 are two-to-three-word phrases that start with a hard "k" sound (Kangaroo Catapult, Cockblocking Cantaloupe, Colostomy Coffee Pot).
Alisa and her father Black Nebula in Episode 13. Nebula releases the trapped squadron, who he was going to eat, if Fuyuki agreed to be Alisa's boyfriend, which he has no trouble accepting.
All There in the Script: Aki's husband stuck in the Hinatas' basement, who was eventually confirmed to be Todd Sirkowski, was originally written in the SFA2 script as "Haru", the Fan Nickname for the unseen Hinata patriarch in Sgt Frog.
Alternate Continuity: The in-universe explanation for SFA1R, SFA2R and SFA3R is that they are how the timeline was going to be before Future Kululu began time-hopping. Out-of-universe, the writers just didn't like them.
American Accents: Pururu is given a Brooklyn accent. It's actually voice actor LillyLivers' natural accent.
Angrish: Tamama's incoherent babbling to Giroro in Episode 8.
Arc Welding/Continuity Creep: The series started with the intent of being as Negative Continuity as the original. Then Episode 10 arrived and, alongside a heaping helping of retcon, developed its own plots and subplots. As creator Yoshi put it:
Artifact Title: Defied with SFA: Reset. Reset was originally going to be the title of a second SFA series, but the title would have lost its meaning right after the first episode, so it was simply shortened to a special as a lead-in to SFA Season 3.
Keroro (and occasionally other characters) have random bouts of Spanish. While Funimation did this with Angol Mois just for laughs, The Midnight Frogs did it because project leader Yoshi is actually Dominican.
Fun with Subtitles often happens at the same time, especially in cases where the supposed Spanish is actually gibberish, or is an actual Spanish statement being passed off as gibberish. Episode 1 also featured Spanglish interplay between Keroro and the caption.
Keroro: "Soy un major yes." Caption: I am grande si.
Future Kululu's random placement of the numerals 4 and 9 become hints when the Japanese language is involved.
Keroro uses Morse code in Episode 12 to send a message to Giroro. It's assumed that he's sending the Serious joke he is saying at the same time; he's actually tapping out Dororo's catchphrase, "I'm lonely".
With the remake of Episode 1, Kululu's brief appearance at the beginning turns into one when the viewer reaches Episode 10.
In Episode 2, Fuyuki thanks Keroro after singing a song, though Keroro can't hear him. In the Post-Credits, Keroro suddenly says "No problem, Fuyuki!" and has no idea why he said it.
The Episode 8 Post-Credits includes a voice saying "Dang, man! Mop need him a cigarette!" The end of Episode 10 features a mop coming out of nowhere and saying "And I'm a talkin' mop!"
The Narrator also leaves early-on in Episode 10 to get some dollar store cheese. Future Kululu's base turns to be a dollar store. Also, the credits feature Mop screaming "Cleaning up the cheese! CLEANING UP THE-"
One of Tamama's invasion plans in Episode 9 is putting cake into the Hinata house's fridge. Later, Kululu finds cake in Keroro's fridge.
Everyone goes on a picnic in Episode 10, with Dororo insisting on holding hands. Later, Giroro seems to freak out after reading Keroro's letter to them, with Dororo saying "See? this wouldn't have happened if you held my hand."
In Episode 6, Dororo temporarily loses his sight and wonders if it has something to do with the coffee. In The Stinger for Episode 12, HQ tells someone to "fix the coffee machine; I think it's making me blind".
Episode 13 has Keroro remarking the object delivered from HQ was not what he wanted for his birthday, first referenced in Episode 6.
Canon Discontinuity/Retcon: The original first three episodes were remade in the interim between Seasons 1 and 2, with the originals being renamed 1R, 2R and 3R, the "R" meaning Retconned. Episodes 1 and 2 were remade simply to make them better and more in-line with the now-developed writing style and quality, and Episode 3 was remade to fix some plotholes that resulted from the first two remakes.
Giroro and Dororo become closer friends at the end of Episode 7. By Episode 11 it's much more noticeable in how the two back each other up at different points in the episode, and in the Episode 14 Post-Credits Dororo asks Giroro to marry him in a very idiosyncratic way.
After having an episode-long daydream in Episode 9, Tamama decides that she is happy being the submissive one in her relationship with Keroro. This doesn't stop her from laying out everything that annoys her about Keroro right to his face in Episode 12.
Keroro's selfishness and poor treatment of his friends causes Fuyuki to break down emotionally and lay out "The Reason You Suck" Speech. Though Keroro doesn't immediately act any different, he seems to respect Fuyuki more the following day.
Character Filibuster: Keroro and Fuyuki each give one to each other in the series finale.
Keroro's personality didn't truly develop until around Episode 3, with Episodes 1R and 2R having him simply be a weak parody of the original.
Kululu's personality also mellowed out considerably after the first season, becoming more apathetic than Jerkassy.
This was the personality the team originally intended for him, but when Jpace92 became his VA they went the creepy jerk route. Then Future Kululu happened, and they steadily went back to making him apathetic.
The constant appearance of the numerals 4 and 9 ("What is this code?!"), his bizarre demeanor through the second half of Season 1, him suddenly disappearing from Tamama's office in Episode 9, and his ethereal cackling throughout Episode 10 all culminate in Future Kululu's reveal in the climax of Episode 10.
Tamama, upon Keroro introducing him, calls himself "a pretty princess" in Episode 2. Then in Episode 8, Giroro reads a joke from Jimmy Carr about vaginal pain, during which Tamama can be heard groaning "ow". Tamama also remarks about having "air boobs" in Episode 9, then later discovers a "hole" in the Post-Credits. The end of Episode 10 is Tamama revealing that "he" is actually a "she", with her attempting and failing to do so throughout the episode.
Season 1 ends with Tamama revealing that he is really a girl and HQ leaving a message revealing that they're sending someone out to get rid of Keroro.
Then Episode 11 ends with Pururu contacting HQ, revealing that she is a double agent. Episode 12 has HQ calling to send out a bioweapon to take out the platoon.
The Kiruru counter appears at the end of Episode 13 with the platoon trying to figure out what it's for.
Dororo proposes to Giroro in the Post-Credits of Episode 14. Giroro's answer isn't given, but Episode 15 opens by making it clear that he said "Yes".
Cloud Cuckoolander: Every character is "off" to some extent. Fuyuki, Tamama and Aki straddle the line between this and The Ditz, and Dororo straddles the line between this and serious mental illness. Even the Straight Man/Only Sane Man characters of Giroro and Natsumi have their weird moments.
Continuity Nod: Jokes and quotes often reappear in later episodes, usually in an altered form. Proper Running Gags are listed further down the page.
Lil' Keroro describes something as "shooty Deus ex Machina" in Episode 7, which was previously used as "shitty Deus ex Machina" in Episode 4, notably the previous flashback episode.
In Episode 4, Dororo asks Koyuki if Earth ever stops having a full moon, which she flatly responds "no". In Episode 9, Dororo asks the platoon if any of them can actually read; Kululu flatly responds "no".
Dororo seems to briefly lose his sight in Episode 6. When it is discovered in Episode 11 that he has every disease ever, Pururu asks if he can even see. He responds, "Usually".
Giroro mentions (and shows) that flashbacks make him nauseous. Come Episode 11 he is around for both flashbacks, and he promptly reminds us of his little weakness.
As Keroro begins the How We Got Here flashback in Reset, Giroro proudly proclaims that he's "conquered it", 'it' being the nausea.
Keroro took Mois to a "dollar store" when she was a child; Future Kululu's base is a dollar store.
Pururu finds Tamama inexplicably tied to a tree in Episode 11. In Episode 12 the platoon ties Kululu to the ceiling; Pururu remarks to Keroro, "I think your platoon is addicted to rope..."
George Albert Nishizawa's first appearance is him acknowledging Todd's Toilets' hot air balloons from Episode 1 and the George Albert radio commercial in Episode 6.
Internal Homage: Keroro begins an invasion plan in Episode 3 with "We're gonna take a can of soda..." In Episode 13 while at a Halloween festival, he repeats that exact line to the others before the camera cuts away.
In Episode 2 Fuyuki laments that girls aren't attracted to him with "What happened to my game...?" In Episode 13 Alisa kidnaps him, causing him to triumphantly shout "I got my game back!"
Episode 14 has several nods to Episode 4, due in part to it being a flashback to the events leading up to 4.
In Episode 15, a delirious Keroro remarks to Fuyuki "I'm your uncle, and I heard what you said", a Call Back to Fuyuki lamenting about not having an uncle in Episode 5.
Also in Episode 15, Keroro tells Giroro that his brother is coming to Earth, but "bad news, he won't make it to Christmas." In Episode 17, Garuru sends a message to the platoon, "Sorry I missed Christmas."
In another Continuity Cavalcade moment, Keroro drops the sudden revelation that he was sold as a child; he is hinted heavily to be the little brother Dororo said he sold for cash in Episode 8. Apparently the cash was spent on Viper's bail in Episode 7.
Kululu sings a "HEGH" harmony at the United Nations in Episode 12. He briefly does the same thing in Episode 18 before singing a Pre-Ass Kicking version of the birthday song to Tororo.
The Todd's Toilets balloon from Episode 1 reappears in Episodes 17 and 18.
Credits Gag: Every credits sequence includes a message at the very end after the ownership disclaimer, usually a follow-up to a joke, a thank you to cast members, or just a something general from the creators to the viewers. Season 2 also lists Let's Player MrFailGame in the credits as a figure or object that either does not speak or does not even appear to begin with.
Averted for most of the characters, though Tamama is a weird example. He starts out being an aversion, unlike both the Japanese and Funimation versions of the original series, but he is revealed to be a girl in Episode 10, becoming both a subverted/straight example and a complete inversion of the original's crossdressing voice.
Giroro also "attempts" this himself by pretending to be Sumomo.
Young male character Private Taruru is voiced by female VA LillyLivers.
Cross Over: Fuyuki appeared briefly in both of TheMidnightFrogs' Pokemon one-shots, and Birdy from Thorn's Jetters Abridged interviewed the platoon in Episode 9 and left a message about Jetters Abridged in the Post-Credits for Episode 13.
Deadpan Snarker: Everyone at some point. Rule of thumb: if ThornBrain voices a character, this is guaranteed to happen.
Debut Queue: The first five episodes introduce a handful of the main cast at a time: Keroro and the Hinatas in Episode 1, Tamama and Momoka in Episode 2, Giroro and Kululu in Episode 3, Dororo and Koyuki in Episode 4, and Mois in Episode 5.
Deconstruction: Fuyuki's monologue in Episode 18 is this for the entire series. Watching Keroro be a Jerk Ass to his friends may be funny, but the scene reveals just what effect this has on everyone around him, and it's not pleasant.
Deliberately Cute Child: Both Mois and Koyuki have played up their cuteness to get the attention of their respective love interests.
Demoted to Extra: Mois, due to her voice actor often being busy, and the writers getting anything they could have really gotten out of the character in her first episode. She still has the occasional line, and the season finale features her more prominently, but overall the writers just never have a use for her.
Dororo was mentally, emotionally, and often physically abused by Keroro and Giroro throughout his life, developing an obsession over them and becoming generally unstable. After he and Giroro began connecting, Dororo was finally able to break from his obsessions and issues to settle into a happy relationship.
After constant threats of death, intense fights with the Garuru Platoon, and friendships being tested and strained, the Keroro Platoon actually take over the world, and nothing can threaten their safety anymore.
Bittersweet Ending: Only because everyone on Earth is time-locked, and everyone else in the universe is dead, including any friends and family they might have had on Keron.
Fuyuki: "Tear down this school!" *Proceeds smacking his body into the roof*
Natsumi: "Alright, let's get this over with. Who and what are you?"
Tamama: "I can't find my ass..."
Koyuki: Jumping through the gym window.
Dororo: Keroro struggling to remember his name. Or care that he's back.
Paul: "Karate Butler Paul at your service. Would you like a cup of tea? I can brew it with my bare hands. Or perhaps you would like a slice of cake? I can bake a cake just by looking at it. Mrrrr."
Garuru: Giroro calling him a "warm-hearted bastard".
Zoruru: "You're looking at me? What- You think we're dating or something?!"
Zoruru is the clear evil counterpart to Dororo: where Dororo is friendly and always feels alone regardless of if people are with him, Zoruru is a cold-blooded assassin who is always alone but feels like people can never leave him alone.
The rest of the Garuru Platoon are subversions. Garuru is out to invade Earth just like Keroro's initial mission, but he is so warm and friendly that, if Giroro were still in the Keronian military, Garuru would be the good counterpart by comparison. Taruru isn't much of a threat, and he's at least as clueless as Tamama. And Kululu's counterpart Tororo, despite possibly being dangerous, is really just unhinged over his father more than anything.
Dororo blames his massive friendship and emotional issues on his parents.
Keroro also blames his parents for setting the stage for everything to go wrong in his life.
Follow the Leader: The series inspired at least two other (now defunct) Sgt Frog abridged series, according to those series' creators: Bokegaeru Productions' Sgt Frog: The Other Abridged Series and AbridgeShion's Keroro Abridged.
Gratuitous Spanish: Yoshi has a habit of breaking into random Spanish when voicing Keroro with expected effect. Many other characters have also slipped into Spanish at points.
Viper. Poses a threat to the platoon at first, but simply being flabbergasted by Dororo causes him to give up.
Same with Future Kululu, who simply leaves after three impossible things happen right in front of him.
Heroic BSOD: Though Keroro was hardly the hero anymore by Episode 17, he suffers a BSOD after being blamed for the world's communications being hacked.
How We Got Here: SFA: Reset begins after everything has happened. Since Mois wasn't there and is confused by the platoon talking about it, Keroro has to flashback to explain everything.
Knight of Cerebus: Subverted with the Garuru Platoon. Garuru's deep, dramatic, threatening voice; Zoruru's nightmarish attitude; and the platoon being the first genuine threat ever certainly take the show into darker territories than before. However, Garuru clearly does not take himself seriously, Zoruru is too messed up to be effectively scary all the time, and Taruru and Tororo are essentially useless.
Large Ham: Keroro, Kululu, Garuru, and the occasional bit character, all to varying degrees.
Logic Bomb: Garuru, under the mistaken impression that Keroro is a military genius, fights a few mental battles with himself before ultimately snapping after this:
"Still, you'll never beat my clever mind. Unless you're more clever- *brain electrocutes*"
Viper is Dororo's father. Or is it the blue frog in Dororo's meditation DVD? It's probably both.
Keroro is Dororo's little brother that was sold for cash as a child, thus making him Viper's son as well. Naturally, Keroro is too dumb to put the pieces together. Dororo has to tell him upfront in Ask GiroDoro SFA.
Major Injury Underreaction: After Keroro slams his fist against a solid stone wall, his only reaction is calmly stating "Huh... I just broke my hand."
Man, I Feel Like a Woman : Subversion. Tamama was probably always a girl, but she only realizes this upon discovering her vagina.
Mood Whiplash: Keroro's monologue in Episode 18 takes the series into dramatic territory for the first time. Fuyuki's response sends the series hurtling into it.
Then Garuru brings it back into comedic very abruptly.
My Name Is Not Durwood: Characters often call Dororo something that starts with the letter "D" (Dorito), is a "Dor" pun (Door Knocker, Doorbell), or is completely unlike his name (Hangnail, Laryngitis).
Lampshaded in Episode 14, when Keroro realizes that he actually got Dororo's name right (immediately after getting it wrong, of course).
Myth Arc: It doesn't get revealed until the end of the first season, but the overarching plot of the series, and the reason the platoon are on Earth in the first place, is that Keroro is useless and people want to kill him for it.
N-Word Privileges: Averted. Keroro outright says "Nig-" in Episode 8.
Never My Fault: The gist of Keroro's monologue in Episode 18. It's what finally breaks it to Fuyuki that Keroro is not the friend he thought Keroro was.
No Bisexuals: Averted overall; deconstructed in Episode 11. Keroro always acted as a Straight Gay while having a very obvious attraction to women, yet when Tamama reveals that she is really a girl, Keroro exhibits a form of "straight panic" and fails to acknowledge that he may simply be Bi. The ending of the episode parodies the LGBT mantra "It's okay to be gay" by saying "it's okay to like''both''men and women". Giroro, the off-screen Wholesome Crossdresser, had this figured out from the start and gets irritated at Keroro's blatant ignorance.
Out-of-Character Moment: Kululu consciously drops his creepy demeanor to bring Tamama back to reality in Episode 9. He only did this because Tamama was being particularly out-of-character himself. Justified in that the whole thing was Tamama imagining if he were dominant in his relationship; he very much is not, and it got very out of hand for everyone.
Kululu works his way up the Nishizawa Corporation, nearly making it the leading world economic power in the process. Soon he finds himself addressing the leaders of the world, whereupon he...sings a "HEGH" harmony. He's back with the platoon the next day.
Saburo is played as mute, or at least he never gets the chance to speak. Let's Player MrFailGame is listed in every Season 2 episode as a person or object that never speaks. When Saburo finally gets a line in Episode 18, it's voiced (for real) by MrFailGame.
Pet the Dog: Giroro, both as a child and as an adult, offers Dororo/Lil' Zeroro drinks in Episode 7, an important point in their Character Development.
Plot-Relevant Age-Up: Every flashback involves Lil' Zeroro saying something that causes Lil' Keroro and Lil' Giroro to instantly hit puberty. Keroro lampshades this the first time it happens in Episode 4, but every time after he just runs with it.
A variation in Episode 7. While the characters cuss profusely as adults, their young selves avoid cursing throughout the episode until Zeroro meets Solid Snake and screams out the F Strike in terror, whereupon Keroro and Giroro immediately hit puberty and begin cussing.
Fuyuki drops one while tearfully berating Keroro for his selfishness and poor treatment of his friends.
Reality Subtext: Subversion. Writer Thorn came out during production of Episode 11 as a bisexual transvestite, but he states that he has always been an LGBT activist, so the series' examinations of sexuality were likely to happen anyway. He does however acknowledge that making all of the characters bisexual and making Giroro a Cross Dresser is Hilarious in Hindsight.
The series overall is a subversion in stark contrast to the original series. Yoshi and Thorn subscribe to the idea that if you can come up with your own joke, it'll be funnier than making a reference. (Not that they don't make references, but they're few and far between, especially when compared to the original series.)
Solid Snake is a straight example. Practically every one of his lines is a quote from Metal Gear Solid 1 and 2.
The numerals 4 and 9 appear frequently in random places and dialogue. Revealed to be a message from Future Kululu that he is going to kill Keroro. The numbers continue appearing after Future Kululu returns to his time. They are also apparently the price Keroro was sold for as a child: $49.99.
Schoolgirl Lesbians: Though the original series features at least three distinct girls with a crush on Natsumi, SFA has every girl in her school obsessed with her, including the teachers.
The Ask GiroDoro SFA audio blog. Initially conceived as a Spin-Off before Thorn decided to end SFA, after which the blog continued the story. It also became a Prequel to SFA Season 3 via the Sgt Frog Abridged: Reset special.
Several messages at the end of episodes in Season 2.
Subverted in the series finale credits. It really is the end. Except, as of February 2013, it isn't.
Set Right What Once Went Wrong: The Reset special is centered around fixing the events in Episodes 16 and 18 that doomed the universe (and prevented the series from continuing).
Reporter: "We are live at Generic Japanese Bridge, where a live seal-"
Person off-screen: "No, it's a Pikac!!!"
Keroro's line "Huh. I just broke my hand" in Episode 9 is a Shout Out to Koyuki-voice actor Revy Moonshine's Patlabor the Abridged Files Movie.
Future Kululu's pencil mustache was inspired by Ron Mael's signature mustache since the 80s.
While Solid Snake provides plenty of Metal Gear references on his own, the message left by HQ in the Post-Credits of Episode 10 is a Shout Out to similar sequences at the end of Metal Gear Solid credits.
Kululu: "I'm gonna go watch Matlock; I don't need this crap." (Though Yoshi and Thorn have never seen Matlock, Thorn has watched The Andy Griffith Show since he was little.)
Giroro's poem at the end of Episode 15 quotes a You Tube Poop by team member Vorhias.
Silence Is Golden: Several outside shots in Episodes 17 and 18 have no sound unless it's caused by the cast, so as to show that the world has indeed stopped dead in its tracks.
Singing Voice Dissonance: Sumomo is voiced by 1KidsEntertainment with a deep rasp when speaking, but she has a clean, feminine singing voice provided by LillyLivers.
"A Pekoponian Day in the Life" - A mostly non-humor parody of The Beatles' "A Day in the Life". John Lennon's parts are sung by ThornBrain from the perspective of a human as the Keronian army invades; Paul McCartney's section is sung by Yoshi from the perspective of Keroro on an average day.
"Pretty Girl's All Mine" - Parody of Chris Isaak's "Pretty Girls Don't Cry". Sung and performed by Thorn from the perspective of Giroro, singing about his crush on Natsumi.
"The Lonely Dance" - Parody of Men Without Hats' "Safety Dance". Sung by ThornBrain as Dororo with RevyMoonshine making vocal cameos as Koyuki. Dororo tries to pretend that he doesn't need his former friends, only for him to have catastrophic emotional breakdowns in each chorus.
"White Blanket" - Parody of "White Christmas", sung by Dororo about wanting a security blanket due to being lonely during the Christmas season.
"Giroro's in Natsumi's Room" - Parody of "Santa Claus is Coming to Town", sung completely out-of-time by Keroro and with incoherent lyrics.
"Walking in a Mall at 12 O'clock" - Parody of "Walking in a Winter Wonderland", sung by Fuyuki about dangerous Black Friday shopping.
"I'll be Home for Christmas" - Sung by Dororo about how nobody ever notices him, not even in his dreams.
"Baby, It's Cold Outside" - Sung by Natsumi and Giroro, with Natsumi trying to get Giroro to leave her room.
"Durdeedeedur" - Also a parody of "Santa Claus is Coming to Town", sung by both Yoshi's and Thorn's respective Tamama's, with even more incomprehensible lyrics than Keroro's version.
"Carol of the Kululu" - Parody of "Carol of the Bells", sung by Keroro, Tamama, Dororo, and Giroro about Kululu and how he acts. It is the only song that does not utilize a karaoke track.
"The Valentine's Parody" - Parody of Billy Joel's "The Longest Time". Sung by Yoshi as Keroro with Thorn singing cheap backup as Giroro and Dororo. Keroro sings a Valentine's song for Tamama, alternating between being a romantic, a cheap date, and a general Jerk Ass.
The team also recorded a parody of The Beatles' "Yellow Submarine" way back in December 2009 called "Tamama's Titties". It was based on an in-joke involving Tamama with breasts, and though Thorn still has the file, it is not available to the public. It and the in-joke it was based on, however, did influence the direction the team would take with Keroro and Tamama's relationship.
So Proud of You: Garuru to his little brother Giroro, though for mundane things like when he taught Giroro how to read. Subverted however: it drives Giroro nuts.
Natsumi: "You know, he seems like a pretty nice guy." Giroro: "But he's so supportive!!!"
In Episode 8 - instead of the usual "woosh" that would be used in such a situation - Kululu slides into frame with a rubbery stretching sound.
Tamama makes a similar sound when turning to face Taruru in Episode 17.
Spell My Name with an S: The series goes with the "Kululu" spelling and pronunciation of said character's name. They also usually emphasize the second syllable in Giroro's name, and they spell the "Sgt" in the series' title without a period.
The Stinger: Every episode features two brief clips after the credits (referred to as Post-Credits), usually following up a joke or situation earlier in the episode, or filling up a plothole. They also served as Sequel Hooks from Season 2 on.
The entire 2010 Christmas special, from the bad singing on most characters' parts to the mostly-unedited background video malfunctioning and looping halfway through.
The "cartoon" in Episode 8.
Giroro's song to Natsumi in Episode 18. Or anytime he sings, really.
Parodied in Episode 7 with Lil' Giroro. The character did not have a line in his first appearance, so when he speaks Lil' Zeroro is shocked.
Saburo in Episode 18
Suicide As Comedy: In Episode 16, Keroro suggests number 4 on his drop-down list of backup escape plans. Number 4 leads to suicide by gunshot to the head.
The point where it gets taken to an extreme is when Keroro then tells Kilili to "spread [his] teachings across the galaxy", which leads to mass ritual suicides on every planet in the system.
Axe is lampooned again in Episode 8, when Keroro randomly reads a section of article in his animation manual that states "Axe spray does not work".
In Episode 8, Tamama asks from where Kululu stole the anime backgrounds. When Kululu simply answers, "It was Haruhi", the platoon is so disgusted that they lose all motivation to work on the project.
Keroro gets a job selling coupons in Episode 10: "Sad thing is, I still make more than Wal-Mart employees."
They Do: Dororo and Giroro in the Post-Credits of Episode 15. Kululu acts as minister. Hilarity Ensues.
Literally with Todd's Toilets and the kids hiding in the train bathroom in Episode 7. Joke-wise the series averts this for the most part.
George Albert Nishizawa spoke to his stockholders in urinal puns during Episode 12.
Too Kinky to Torture: Natsumi is frequently hinted to have an interest in bondage and/or rape. No longer used as a gag in Season 2.
Two Lines, No Waiting: Episode 12 alternates between Kululu working at the Nishizawa Corporation and everyone else being terrorized by his cursed DVD at the Hinata house.
Yoshi's Keroro voice started out as him trying and failing to emulate Todd Haberkorn and instead just talking like himself. Circa Episode 5 his Keroro voice no longer has Haberkorn influence and is now him...just talking like himself.
Jpace92's Kululu gradually became rougher and more sinister after his first appearance. Even his casual lines sound disdainful now.