As Nijigasaki has a whole 3 years of backlog material to reference, this is to be expected.
Animated Singles
- "Muteki-kyu Believer" references all of Kasumi's cards from Love Live! School Idol Festival ALL STARS at the time of release, including her unidolized "Magical Fever" UR and her idolized "Exciting Animal" SR.
- The PV features plush toys that reference the Famitsu App Yonkoma such as Ayumu's pet snake Sasuke, the Martians that become Ayumu's fans, the evil spirit that possessed Ayumu (before Nozomi exorcised her), the tsuchinoko that Ayumu caught, the God of School Idols, and the spaceship that Ai, Rina, and Ayumu flew.
- The rainbow koppepan is a reference to this comic
for April Fools' Day 2020. - The "Mirai Harmony" MV features all of the girls performing their solo SP Skill poses from the game during the chorus.
Anime Season 1
S1 Episode 1
- The buns that Ayumu and Yu eat throughout Episode 1 are based on a "Kasumi's koppepan recommendations" list that was released as part of the April Fools' Day 2020 joke.
- The scene of Setsuna performing "CHASE!" replicates some of the camera angles used in the music video performance from the game.
- Sasuke, Ayumu's pet snake from the early Famitsu Yonkoma appears as a plush in Ayumu's room, just like in the "Muteki*kyuu Believer" PV.
- Yu's personal ringtone for Ayumu is an instrumental version of "Yume e no Ippo". Her contact picture is also a shot taken from the "Mirai Harmony" PV.
S1 Episode 2
- Kasumi ends up using the same glasses + facemask disguise that Nico and Yoshiko used previously in School Idol Project and Sunshine!!, respectively. Bonus points for Kasumi more or less being a Nico Expy.
- When Kasumi goes to reinstall the School Idol Club's nameplate on the door of the club room in Episode 2, she finds that it's been replaced by a club called the Wandervogel Club. This references Chapter 1 Episode 2 of ALL STARS, where the protagonist enters the School Idol Club's room and Kasumi assumes that the protagonist is a member of the Wandervogel Club (subtitled "camping club" in the English version) that intends to take over the club room after the School Idol Club is dissolved.
- Hanpen, the cat that Rina ends up adopting in her ALL STARS Bond Story, appears in Episode 2 as the cat that Kasumi throws at Nana and is later seen being fed by Ai and Rina.
S1 Episode 5
- The magazine seen on Karin's desk in Episode 5, "High School Idol", is the same magazine that Honoka shows to Umi and Kotori in the first episode of School idol project. Interestingly, the number on the cover indicates that the edition that Karin owns is the 8th publication, while the magazine used by Honoka is the 5th.
S1 Episode 6
- Episode 6 opens with Yu, Ai, Ayumu, and Rina playing the ZERO LATENCY VR game at JOYPOLIS Tokyo and fighting pudgy grey bird enemies. This one's a double reference; the scene is based on a 2018 episode of "Abema TV Ultra Games" where the voice actresses played the VR game "Zombie Survival" at the location, and the enemies are based on similar-looking birds who attacked Ai and Rina in the Famitsu Yonkoma.
- The background music heard when Rina is introducing herself at her concert in Episode 6 is an instrumental version of "Analog Heart", Rina's solo song from the Nijigasaki 3rd album "Just Believe!".
S1 Episode 7
- Haruka is seen holding a cup with the "Pocky" branding on it, a nod to the fact that her birthday is November 11th, also known as "Pocky Day".
- Haruka's lack of cooking skill is referenced in Episode 7 when she botches an attempt at rolled egg at the end of the episode.
S1 Episode 8
- Episode 8 has a scene where Shizuku looks at a poster for a movie named "Audrey", which shares its name with her second solo. She also quotes the title of her first solo, "Anata no Risou no Heroine", at the beginning and later on. Appropriately, the lyrics of both songs are strikingly similar to how Shizuku's character develops throughout the episode.
S1 Episode 9
- The Gamers store that first appears in episode 9, where Yu, Ayumu, and Setsuna meet Karin, is basically a complete replica of the store from the inside out. One of the posters on the store windows is identical to a poster seen in School idol project's own Season 1 Episode 9 when Honoka and Umi chase Kotori around Akihabara.
- The school idol merchandise of Touou and Shinonome idols uses School Idol Festival's old card backgrounds and name-banner style.
- The first-years are seen about to eat macarons in Episode 9 when Setsuna messages the club members about Karin's decision. Macarons are used to upgrade cards in ALL STARS, and the macarons seen in the anime are identical in color to the ones seen in the game.
- Himeno Ayanokoji is seen wearing the outfit from her first idolized N card in Episode 9.
- The Shinonome school idols mimic their N card poses from School idol festival during their stage introduction at Diver Fes in Episode 9.
S1 Episode 10
- Episode 10 is the series obligatory summer training camp episode, much like how School idol project and Sunshine!! held summer training camps in Episode 10.
- Episode 10 has a shot of the girls looking at the sky at dusk and seeing a shooting star. This is similar to the rare Training Camp animation in ALL STARS where shooting stars cross the sky at nightfall when a card gets an Insight at the end of Training.
- Setsuna mumbles her call and response line, "Setsuna Scarlet Storm", in her sleep after knocking Kasumi out in a single blow with a pillow.
- The Touou Academy school idols can be seen mimicking their N card poses from School idol festival when Yu clicks on a video of them in Episode 10.
- Emma's swimsuit in Episode 10 is based on an image of her in a swimsuit from the comic tapestry series. Shizuku's swimsuit is based on her unidolized "Miracle Voyage" UR, while Setsuna's swimsuit is very similar to the one she wears in ALL STARS Chapters 18 and 19.
S1 Episode 11
- Episode 11 has Kasumi popping in from the right corner of the screen in one scene, emulating the "photobombs" that Kotori and You did in the original and Sunshine!!.
- Four of ALL STARS's "Exciting Animal" outfits are displayed on mannequins in the costume club. One of its club members shows Emma's Evergreen outfit on a tablet.
- During a particular shot inside Yu's room in Episode 11, a framed picture of a younger Yu depicts her wearing a Fun Shirt in the style of Honoka and Chika's, with "ぱ." written on it.
S1 Episode 13
- Episode 13 has Emma doing a photobomb this time, peeking out from the bottom left while someone takes photos of Karin◊.
- Setsuna calls out her "Setsuna Scarlet Storm" phrase out loud for a stage play with Kasumi and Shizuku.
- A giant Sasuke, Kasumi's pet mouse, and Rina's robot cat Aran appear as fighting game characters in Episode 13.
- The logo for the School Idol Festival that is briefly seen on a flyer in Episode 13 bears a striking resemblance to the logo for Love Live! School idol festival.
- At one point, Emma is accompanied by several children in Episode 13, referencing the children who accompanied Maria Sashide on-stage during the live performance of "Koe Tsunagou yo" from "First Live with You".
- The stage for "Yume ga Koko Kara Hajimaru yo" is based on the Nijigasaki stage in ALL STARS.
- Three stills near the end of Episode 13 have the club members standing with their subunit groups (DiverDiva, QU4RTZ, and A•ZU•NA) in the poses for their first-single covers.
- Another three stills have the girls posing for the camera in identical fashion to their voice actresses taking backstage photos from Nijigasaki 2nd Live.
S1 insert song outfits
- Much like "Muteki-kyuu*Believer" for Kasumi, most of the anime insert solos (except Setsuna's) feature various character outfits from pre-anime songs and ALL STARS.
- "Dream with You" features Ayumu's costume for "Yume e no Ippo", the outfit from the cover of A•ZU•NA's first single "Dream Land! Dream World!", and the "Sweets Deco" UR.
- "Poppin' Up!" features Kasumi's "Flower Symphony" UR, "Magical Fever" UR (idolized, unlike "Muteki-kyuu*Believer"), and her outfit for "Diamond".
- "Saikou Heart" features Ai's unidolized "Marching in Harmony" SR, unidolized "Excited Animal" SR, her "Meccha Going!" outfit, and her unidolized "School Girl Heartthrob" UR.
- "La Bella Patria" features both versions of Emma's "Delightful Waltz" UR, the "Innocent Red Riding Hood" UR, and her "Evergreen" outfit.
- "Tsunagaru Connect" features a quick scene of Rina in her "Dokipipo Emotion" outfit and the outfit from her "Emotive Signals" UR. In addition, the choreography references the "scuttle walk" she does in "Dokipipo Emotion".
- "Butterfly" features a short scene of Kanata watching still images of herself, which include anime recreations of her "Nemureru Mori ni Ikitai" and "Angel's Lullaby" cards as well as a Super-Deformed image of her in her sleeping bag from the older Yonkoma.
- "Solitude Rain" features Shizuku's unidolized "Rose Knight" UR (including the dog), her "Exciting Animal" SR, and her "Miracle Voyage" UR. Two of her outfits are also from one of her N cards from Love Live! School idol festival, specifically the 2013 "Innocent Declaration!" event card. One of the scenes additionally references a Yonkoma where Shizuku downs a bowl of dandan noodles in her N card jogging outfit.
- "VIVID WORLD" features the outfit Karin wears on the cover of DiverDiva's first single "SUPER NOVA", both outfits from her "Tentation Blue" UR, her "Celebrity in Blue" UR, and her unidolized "Rainbow Rose" SR.
- "Awakening Promise" features recreations of Ayumu's "China Maid", "Exciting Animal", and "Present For You" cards, with similar poses.
Anime Season 2
S2 Episode 1- Season 2 Episode 1 shows all ten of Kasumi's koppepan versions from the April Fools' Day 2020 post.
- Yu has changed her ringtone for Ayumu to an instrumental version of "Kaika Sengen", Ayumu's 2nd solo from the "Love U My Friends" album.
- The club's booth at the Nijigasaki Open Campus has merchandise from Nijigasaki 3rd Live.
- The music video for "Eutopia" includes a lot of bird cage imagery and various lyrics about being Lonely at the Top, both allusions to Lanzhu's characterization in ALL STARS, especially in the later chapters. One of the poses that she makes also references one of Akina Homoto's poses for her agency profile.
S2 Episode 2
- Kanata's opening narration at the start of Episode 2 is lifted from the lyrics of QU4RTZ's first single, "Sing & Smile!!".
- A doodle of the God of School Idols from the Famitsu yonkoma is drawn on the whiteboard.
- The poster for the joint live event in Episode 2 uses the poses from Y.G. International's N cards in SIF (except Emma's, for obvious reasons).
- The Odaiba Gamers store reappears in Episode 2. Various Love Live! and Love Live!-adjacent merchandise can be spotted if one looks very carefully, including album covers for Nijigasaki and Liella! singles, cards from Aqours' live performance of "Omoi yo Hitotsu ni Nare", a poster for the official Liella! food truck, and albums and posters featuring voice actresses from the series.
- The idol training board makes a return albeit it's written in English text but without chart.
S2 Episode 3
- Subunit-focused episodes are named after songs from the groups' first singles. "sing! song! smile!" is named after "Sing & Smile!!", with "Ai Love Triangle" named after "Love Triangle", and "Dreamland is Now Open!↑↑（＊'▽'）" after "Dream Land! Dream World!".
- Rina's suggestion of holding a virtual concert brings an Imagine Spot of QU4RTZ in their "Just Believe!!!" outfits from ALL STARS.
- Yu's unable to compose a music and the entire group tries to comfort her is similar to the player's case in ALL STARS Chapter 7.
- QU4RTZ's stage background features the swing set from the "Swinging!" cover art.
S2 Episode 5
- The School Idol Memorial exhibition has on display a "Love Live! Victory" flag and a trophy. The flag was previously shown in the Season 2 finales of both School Idol Project and Sunshine!!, while the trophy was in School Idol Project.
S2 Episode 6
- In Episode 6, as Kanata and Ai talk about how fans were discussing who Setsuna is, one of the Imagine Spots shows Setsuna with her megaphone from the game's 3D video for "LIKE IT! LOVE IT!".
- Shioriko discovering Setsuna's identity, the members tried to defend Setsuna, and Shioriko keeping her promise from revealing her secret are all similar to the last episode of Chapter 8 in ALL STARS.
- While trying to cover for Setsuna, Shizuku borrows her catchphrase, "Setsuna Scarlet Storm", and says, "I saved the world today!" This is part of Tomori Kusunoki's (Setsuna's voice actress) call and response during live concerts.
- First shown after A•ZU•NA's live show, on the outdoor displays and banners for the 2nd School Idol Festival, the cursive font is similar to the ALL STARS logo text, plus the yellow circle behind the text.
S2 Episode 7
- In Episode 7, Ai and Rina wear their "Exciting Animal" costumes from the game at Touou Academy. Later on, Ayumu, Ai, and Setsuna perform in their "Rainbow Heart" costumes at Shion Girls' Academy.
S2 Episode 8
- The Season 2 Episode 8 performance of "TOKIMEKI Runners" uses many of the same stage elements and camera angles as the in-game music video from ALL STARS, specifically the Season 1 Chapter 17 version of the song. The girls are additionally dressed in their very first performance outfits from the "TOKIMEKI Runners" album. It is also the only song in the anime to be animated almost entirely in CGI, alluding to how the game uses 3D animated performances.
S2 Episode 9
- Mia's opening narration for Episode 9 uses lyrics from her single "I'm Still..." but spoken in Japanese.
S2 Episode 10
- In Episode 10, Rina's Augmented Reality smartphone game, "NijiGaku GO", features 13 cat designs that represent all the club members. Ten of these cats are from "Nyangasaki", a series of April Fools' Day 2021 posts that featured the first ten performing idols (including Shioriko) as cats.
- The games Kasumi gets everyone to play once they arrive at Shizuku's house are a reference to some of the games the cast played in a very early series of specials where they competed for the title of Abema TV Ultra Games Image Girl (also referenced above in Season 1).
S2 Episode 12
- Overlapping with Ret-Canon, the after-credits scene of Episode 12 reveals that "Nijigasaki First Live with You!", the name of an actual live concert in 2019, is the name of the club's first big concert in the anime.
S2 Episode 13
- In Episode 13, as Mia and Lanzhu suddenly decide to join Shioriko on stage, one of the stills shows the trio by the stage stairs in the poses for the R3BIRTH "MONSTER GIRLS" single cover.
- In the epilogue, Ayumu sends Kasumi some texts along with two stickers of herself in the Famitsu yonkoma's art style. They also include her pet snake Sasuke.
S2 insert song outfits
- The anime insert songs continue to feature various character outfits from ALL STARS and songs made before this season premiered:
- "Eutopia" features Lanzhu's "Queendom" SR outfit and includes an image of the crane stance she strikes at the end of the song in the game.
- "ENJOY IT!" is Reference Overdosed since there are four members. For starters: Emma wears her "Evergreen" UR outfit underneath a beige coat. Kasumi has her "Margaret" and "A Sweet Moment" UR. Rina shows her unidolized "Heart Science" UR sweater followed by her "Checkmate" UR. Kanata's unidolized "Resplendent New Year" UR pose is shown with her "Mysterious Thief K" UR. And then there're the Freeze Frame Bonuses during the "Shake it" chorus.
- "Eternal Light": After the fast starting countdown, shots throughout the video have Karin and Ai wear "THE SECRET NiGHT" cover art's clothes, followed by UR outfits for: "Starlight" and "Meccha Going!!", "Moo Moo Farm Days" and "S.I. Collection", "Signs of Spring", "A Dress to Dream About", "TWINKLE STARRY NIGHT" and "School Girl Heartthrob", and finally "Celebrity in Blue" and "Venus on a Moonlit Night".
- "Infinity! Our wings!!" shows UR outfits including: Setsuna's "Justice Archer", Ayumu's "Say Good-Bye Namida" and "Mystic Fairy", and Shizuku's "Yagate Hitotsu no Monogatari" and "Fluffy-Wuffy Shizu-Bear". Then it shows Ayumu's "Cyber World" and Setsuna's "Jet Black Magician". Finally, there's a quick recreation of the trio's "Maze Town" cover art.
- "EMOTION" features Shioriko's casual unidolized clothes seen on her "Pure and Lovely Moment" UR, "Colorful Knitting!" UR, the SIFAS story (e.g. ch. 27 ep. 6), and "Just Believe!!!" SR. Then her "Pure and Lovely Moment" self walks in on her unidolized "Love the Life We Live" self. Split-second stills during the chorus show her idolized outfits for "Ketsui no Hikari" SR, "Jade-Colored Reverberations" UR, and "Aoi Canaria" SR.
- "TOKIMEKI Runners": Just before the chorus, the second Freeze Frame Bonus picture shows the nine Club members in their "Love U my friends" outfits.
- "stars we chase": As the camera zooms through the doorway, it passes by two duplicates of Mia; they wear her UR outfits for "Autumn Thanksgiving" and "No One Can Manage That Out of the Blue"/"I'm Here".
NEXT SKY
- Shizuku is seen playing with a wall of Kasumin Box plush dolls in a Gamers store, referencing the plushie line that was released as cross-promotion with the Nijigasaki anime.
- The cast stops by The Chara Cafe to discuss their plans for Aira, with all of the main girls having their respective drinks from the shop's real-life Nijigasaki collaboration menu.
