It would be somehow hard to avoid references when an Otaku serves as one of the protagonists, as they tend to speak in shout-outs.
Season 1
Episode 1
- During their honeymoon, Hajime wants to see Kaoru in a swimsuit outdoors, but she winds up wearing it indoors, after which the scene closes with a white square bubble saying "They had lots of sex afterwards", based on the same Japanese Twitter memenote .
- In the anime, Hajime is watching Engaged to the Unidentified and proclaims the character Mashiro Mitsumine is his "wife"; in the manga, it's Hanasaku Iroha instead, as he gushes over Minko Tsurugi.
- When Hajime declares that he has no desire to work, he puts on the face of Himura Kenshin with the same X-shaped facial scar across his cheek.
- When Kaoru takes a look at one of Hajime's porn magazines, she claims that all men are obsessed with boobs. Hajime affirms it and screams a familiar Catchphrase frequented by Setsuna F. Seiei as a parallel while "piloting" from a cockpit:Hajime: "I...We...are boobs"!
- Hajime is watching Magical Girl Lyrical Nanoha StrikerS as he gushes over Nanoha Takamichi. When Kaoru attempts to put on a Moe appearance, Hajime senses its presence via "Newtype spark" with the appropriate sound effect. His facial appearance, especially his eyes, changes as if Hajime has entered "SEED Mode".
- Two of the posters in the movie theatre are of Mobile Suit Gundam Unicorn and Puella Magi Madoka Magica The Movie: Rebellion.
- After they watch the movie, the fisheye lenses heavy Art Shift when Hajime's doing his critic monologue is a shoutout to the Talking Heads scenes of Patlabor 2: The Movie.
Episode 2
- One of the eyecatches shows a picture of Mayotama in a certain pose
with the title "My Little Broster Can't Be This Cute". - Hajime wearing a horse head mask when meeting Kaoru's friends while laughing creepily is possibly based on the half-horse, half-human character Stallion from the Words Worth Eroge. Bonus points for Hajime's voice actor Kenichi Suzumura, who voices the protagonist of Words Worth.
- might also be the Ponytail Stalker in Full Metal Panic? Fumoffu
Episode 3
- The title of the episode is called "My Otaku Brother Can't Have So Few Friends (Etc.)".
- Mayotama wants to do some "Yosuga-ing" with his brother.
- Hajime thinks that his plan for Mayotama making friends should work as long as he's "thinking in Oreimo terms".
Episode 4
- What Hajime quotes at the beginning of the episode is lifted straight from El Shaddai: Ascension of the Metatron.
- He also responds to Kaoru in that same scene with Enoch's Catchphrase "No problem. Everything's fine."
Episode 5
- Johannes Krauser II appears in the background as Hajime mentions how Kaoru acted when she came home drunk. He claims she said that she would "rape him 10 times in one second", based on Krauser's ability to say the word "rape" 10 times in one second.
- Near the end of the episode, Hajime makes a reference to Comic Kairakuten regarding what Kaoru said during her alcoholic-riddled love-making session the night before, the same-named monthly published volume for many Hentai manga artists.
Episode 7
- Hajime's response to Kaoru's cooking is "It's a yes!"
Episode 8
- The title of the episode is Pro Golfer Naru ("I'll Become a Pro Golfer"), a reference to an obscure sports series called Pro Golfer Saru.
- During the eyecatch, Kaoru dresses up as Backbeard and proclaims "You Damn Lolicon!".
- When asked about her favorite golfers, Ai-chan states Bill Rogers and Harry Vardon.
Episode 9
- In the Flashback, Hajime's room contains a figure of Cattleya and posters of Mikuru Asahina as a Playboy Bunny and Eris. A small framed picture of what appears to be Madoka Kaname can also be seen. When Mayotama mentions Hajime forgot to pick up his "Ai Plus" game, the girl on the obvious-looking Nintendo 3DS handheld is Ranpha Franboise.
Episode 10
- When Hajime's mother shows up, the scene is a brief reenactment of the same door scene between Rena Ryugu and Keiichi Maebara.
- When discussing possible names for a child, Hajime pulls the "Gendo Ikari pose" stating, "If it's a boy, Shinji; a girl, Rei", referencing Shinji Ikari and Rei Ayanami.
Episode 12
- At the start of the episode, Hajime's computer has the obviously censored out homepage to Google. To the left of the monitor are two volumes (likely manga) featuring Amane Suou and possibly Michiru Matsushima.
- The first three shots of that same scene (Hajime's PC screen, him sitting in his chair floating in space and a close of him giving the camera a thumbs up) mimic the opening of Mobile Suit Zeta Gundam.
Episode 13
- The Crunchyroll summary for the episode is "Congratulations to all the children": in the episode itself, all the characters re-enact the infamous "Congratulations" sequence at the finale of the television series.
- When Hajime is caught by surprise from Miki at the convenience store, the "Alert Mode" enemy status screen is seen.
- When Kaoru gets an Unexpected Positive for the home pregnancy test, it bears a striking resemblance to the "Pregnancy Announcement Meme".
Season 2
Episode 1
- One of the eyecatches is Kaoru as Pino; before that, Hajime asks Kaoru if her "Runes got eaten" because she can't remember where the ramen shop was.
- Another eyecatch features Nozomu as Ippo Makunouchi.
- The Chinese master chef that Hajime imagines is Liu Mao Hsing.
- While trying to take pictures of high school girls with his phone, Hajime says "Shutter Chance!", referencing Ranko Hata's Catchphrase.
- The "Siri-like" program on Hajime's smartphone sounds exactly like a Dominator.
- After being beat up by Kaoru for saying immature things at his phone's voice search, Hajime ends up in a crater that Yamcha died in when fighting a Saibaman.
- After seeing what she was capable of, Hajime wonders if Kaoru's high school Senpai Akiko was a Terminator.
- The same reference to the "They had lots of sex afterwards" meme occurs at the end of the episode.
Episode 2
- While worrying about her compatibility with Hajime, Kaoru imagines themselves as Sailor Moon and Tuxedo Mask when thinking about communication and Gold Saint Sagittarius and Cancer when checking astrology.
- The "To Be Continued" arrow at the end of the episode is lifted straight from Jojos Bizarre Adventure.
- Hajime can be seen wearing a cardboard Gundam suit and quoting the first two words from the opening theme song of Mobile Suit Gundam.
Episode 3
- Hajime's video game consoles seen at the start of the episode are the Microsoft Xbox One, Sony PlayStation 4 and Nintendo Wii U.
- The figures next to the television are Rika and Mika Jogasaki, except their hair colors are swapped
- The five boxes stacked on top of one another next to the fax machine contain Gundam plastic models, specifically, the top three come from the SD Gundam line (seen via their enlarged, human-like eyes) with the second-from-the-bottom either the GAT-X105+AQM/E-X01 Aile Strike Gundam or the ZGMF-X56S Impulse Gundam and the last one the RX-78-2 Gundam.
- Due to a lack of cleaning, Hajime's room has been turned into the Sea of Corruption and Kaoru is forced to wear the same gas mask like that of Nausicaa.
- Hajime and Kaoru's bowling team is named "TYPE-BOON"; when it's his turn to bowl, Hajime cries out "EXCALIBUR!", mimicking Saber's famous attack.
- Lampshaded in the Crunchyroll summary:
"The body is made of pins. Blood is the ball and the heart is the lane..."
Episode 4
- The episode is called "I Only Draw Free", a reference to Haruka Nanase and his Catchphrase "I only swim free".
- Another video game console, a black-colored Microsoft Xbox 360, can be seen under the television when Hajime and Kaoru are discussing Mayotama's job options, though it is oddly drawn to have two power buttons instead of one.
- According to Kaoru's manga artist Senpai Yuzu, Mayotama's favorite manga is Tokyo Ghoul.
Episode 5
- Hajime's suggested bowling team name for him and Miki is "Little Busters!". In response, Miki states "he has no interest in finding out the secret to the world", a reference to a Plot Point from the Visual Novel.
- At the 2:08 mark of the episode, a sound effect incredibly similar to when a Great Person is born in Civilization V plays can be heard.
Episode 6
- A "(-108)" can be seen beneath the episode number proper; given the majority of the episode is a Flashback, it's most likely referring to the first chapter of the "Turn Back The Pendulum" story arc from Bleach.
Episode 8
- In the Flashback, when Hajime comes to defend Mayotama, he claims the bullies don't seem to be from "The Organization".
Episode 9
- Hajime is seen wearing cat ears and a tail, stating "I'm with the Witches" when Kaoru questions why he's only in his underwear inside their home, with the addition of the sound of a jet plane being heard once he says it.
- When Hajime is handing out Mayotama's new year's allowance, the envelope character looks like the titular Doraemon except green-colored rather than blue.
Episode 10
- Hajime is shown watching what appears to be Himegoto until the eyecatch drops all subtlety and flat out states what it is◊.
- When Hajime and Kaoru are sitting at the table discussing about their past, there's a peculiar straw hat hanging on the wall.
Manga
- I chapter 3, Kaoru and Hajime are playing Guilty Gear together.
- The cover a picture of Kaoru cosplaying as Jam Kuradoberi with Hajime as That Man.
- In chapter 5, Hajime says "I'll destroy that illusion of theirs."
- Kaoru attempts to try and play Yu-Gi-Oh! in chapter 6 but is hopelessly out-of-date with the meta-game. She apparently read up to Yu-Gi-Oh! R.
- Hajime and Mayotama have a Gundam quiz in chapter 7.
- Hajime also refused to go swimming with her because he was busy soloing the final boss of Monster Hunter 3.
- Kaoru imagines buying Yaoi dojinshi of Tiger & Bunny, Reborn! (2004), and Hetalia: Axis Powers in chapter 8. She is also mentioned to have 250 skill points for a double attack.
- In Chapter 42, when Kaoru is thinking how impossible it would be for Hajime to cheat on her, he's watching anime and calls a character his "waifu". Given the character's hat and crisscrossed hairbands, she's very likely to be Kafu Chino.
- While they were going out, Kaoru tried to get Hajime to call her on a First-Name Basis. One of the joke names he gave her was "Kaorin", while he appropriately looked like Mr. Kimura.
- After being scolded for eating the bread that was for breakfast the next day, Hajime asks Kaoru if she remembers "how many slices of bread she's ever eaten". It's noted he did so just so he had an excuse to quote the meme.
- Kaoru is wielding Raising Heart on the cover of Chapter 51.
