Aluminum Christmas Trees: The crazy looking car Kasai owns are a real type of modifications to cars, known as Bōsōzoku cars.
Catharsis Factor: Of all things, how the bank employee scene plays out during this story's take on the Harvest arc. In canon, Josuke's last ditch effort to fool him during his call to Mr. Morishita just leaves him dumbfounded as he has no choice but to drop his suspicion. Here, Fubuki's fake sob story nearly backfires, but Fubuki is able to turn it on its head by revealing his relation tohis mother. This ends up scaring the living shit out of the employee to where he even bows before Fubuki while begging him not to tell his mother about what happened. The fact that he winds up like this instead of having to just eat a Humble Pie can be amusing as it is cathartic.
Considering the Werewolf kidnaps and kills children who are alone, it's a good thing Josuke and his friends found Irene first during chapter 8.
When Katsumi reveals that she was Angelo's lover and accomplice, she does some Evil Gloating in which she reenacts to a restrained Fubuki and recounts what led to Shinichi's fatal wound with sadistic glee. Considering how much Shinichi's death traumatized Fubuki, it angers him so much that all he's able to do is furiously bite her ear, getting it half torn off in the process. One can only imagine how differently Fubuki might have reacted in that moment had he not been restrained (though he unleashes the rest of his anger towards her in a rush attack, also giving Katsumi the honor of being on the receiving end of Purple Rain's first use of its Kiai).
When Fubuki has a hallucination of a dead Sion, it's also a Shout-Out to An American Werewolf in London. It's later mentioned that Fubuki would see this same hallucination again in his nightmares, and if you're familiar with the source material being referenced, then it likely also means that Fubuki's subsequent encounters of this hallucination had Sion looking worse than the last in a very grotesque way.
Fridge Sadness: During the chatter of some students from the aftermath of Miyazaki's death and exposure as the child kidnapper/murderer at the start of chapter 67, one student says they don't have a younger sibling anymore because of him. When you think about it, it can be pretty depressing to imagine a scenario where your younger sibling goes missing and ultimately turns up dead because of a child murderer while you're in high school, which goes to show just how many families Miyazaki tore apart with his killings, especially when you remember that one missing child's mother was seen crying on the news the same night Josuke and Fubuki came across the boxed remains of said child.
Much like Sonny's words on the Zeppeli family in Star-Crossed Crusaders, Grandma Julia's words to Fubuki from the day of Ryohei's funeral can hit much harder once Lacrime D'oro del Vento Aureo reveals just how bad things got for Caesar's siblings. Namely how Julia was alive for all of her siblings' deaths, one by one, and she blamed Fredo for Cornelia's death.
Julia: Nobody in the Zeppeli family has ever died from natural causes, I know it will be the same for me one day. I've buried far too many family members, so when it's my turn to die...I want you and Norisuke to bury me.
Fubuki briefly scolding Irene for getting lost in chapter 8 becomes very wince inducing once the werewolf is properly introduced. Fubuki's concern was actually a very real possibility considering it eats children.
Fubuki: Your father doesn't even know where you are, how do you expect him to find you? You shouldn't have wandered off like that. What if a stranger tries to kidnap you?
Onodera's death predates Yasuho Hirose coming very close to dying in JoJolion, right down to a gruesome injury that leaves her collapsed (Onodera's face disfigured by Kira here, Yasuho losing an arm in JoJolion) and crying for Josuke to help her in some form. Bonus points if you read this fanfic before reading Part 8, as it can make Yasuho's near-death even more heart-pounding. For this kind of reader, it can feel like a Yasuho's death is happening again.
Higura also wanting the 5 million Yen voucher in the Harvest arc can become a lot more pensive once chapter 41 reveals that her mother has a gambling debt of an unspecified amount, and part of the money would have likely helped with it.
Detective Yanagimoto's softer side, such as him giving Josuke Ryohei's watch after his death, and the dinner scene in chapter 48, including him getting together with Tomoko becomes very sad when he physically lashes out at Tomoko trying to see him after his Despair Event Horizon (which causes them to break up), caused by seeing a water clone of Shusuke Miyabe and all the bad press from being unable to find Miyazaki sooner. To top that all off, he's manipulated into going after the heroes by Yoshihiro Kira, ultimately causing his death.
Reimi's belief that Miyazaki wouldn't hurt anybody ends up being a lot sadder when she learns Miyazaki was the werewolf and quietly cries to herself from the betrayal. It's also tragic in how Miyazaki managed to keep his werewolf self hidden from her, and despite their breakup, Reimi still believed in his innocence.
Virtually every scene of Miyazaki being caring to Fubuki either becomes very awkward or depressing when you learn that Miyazaki is the werewolf, and he would ultimately become enemies with the rest of his students. Especially because Fubuki and the others fully believed that he was innocent regarding Reimi's murder.
One particular example is that Fubuki telling Miyazaki about his mother and Miyazaki promising things will get better for Fubuki can be incredibly chillingon a re-read once it's revealed that Miyazaki is the werewolf. Miyazaki essentially thought he'd be doing Fubuki a favor, but as the When Doves Cry arc shows, Fubuki didn't actually want his mother dead despite how she treated him and his last words to her before finding her seemingly dead.
One particular Rewatch Bonus is how Rohan contemplated and decided against using Heaven's Door on Miyazaki and then Yanagimoto for different reasons, which becomes a lot of Dramatic Irony when both are revealed to be Stand users who would attack the heroes. This is especially harsh in Miyazaki's case since it means Rohan came extremely close to learning the identity of the werewolf, which could have prevented a lot of child murders and the When Doves Cry arc.
Josuke's sudden Disney Death after Kira's defeat, while very brief, can be harder to read after Billy Kametz' untimely passing in June 2022. Especially since some of the dialogue in this fanfic series was written with the English Dub in mind, and there was even some Actor Allusion used for Josuke. Even the prior fallout of Onodera's death leaving a lot of the cast shocked and upset about her death counts as well, since it's not unlike how many collectively felt upon initially hearing the news about Kametz, and Josuke losing his love interest parallels how Kametz was dating Erica Lindbeck before his death.
The night Josuke and Onodera get together, Josuke discreetly carves his and her names into a tree. The tree's urban legend says two lovers will meet again in another life if their names are carved into it, and while it's a Call-Forward to JoJolion's Josuke and Yasuho, and that Onodera would die a few chapters later, Yasuho Hirose does indeed survive the part after nearly dying towards the final battle. Keep in mind that the entire fanfic was written while JoJolion was ongoing, so Yasuho Hirose's near-death came dangerously close to making Onodera's death Harsher in Hindsight in the sense of Onodera dying only for Yasuho Hirose to also die.
After Kira's defeat, Ryohei and Onodera appear before Josuke in a dream of sorts one last time, and Onodera mentions that how Bites The Dust works proves the existence of multiple timelines, and that they'll continue to meet in those.Even if that's what Josuke and Fubuki would get warped to (by an enemy Stand user) in Bizarre Christmas of 1999, this would essentially become reality a year later, finally giving Josuke and Onodera that Christmas date they talked about before her death in the original timeline.
The story establishes that when they were children, Fubuki was terrified of Josuke having a mysterious power and stopped hanging out with him after he healed his broken leg, and Fubuki moved away not long after that. Because the alternate timeline that Bizarre Christmas of 1999 is set in shows that Fubuki never moved away, the two were still friends, and that Setsuna is a lot nicer, it's implied that he did get to patch things up with Josuke in that timeline.
In chapter 38, the chapter after Josuke's birthday and hookup with Onodera, Tomoko picks up that Josuke has a girlfriend, taking on a serious tone at first as Josuke tried to hide it. Not long after as Josuke explains who Onodera is, she turns out to be okay with Josuke dating, playfully teasing him about it and even wanting to see Onodera sometime. It's a nice display of Tomoko being a good mother underneath her hot-bloodedness.
Tomoko: So, when do I get to meet this lady who stole my boy's heart? Josuke: Y-you're not mad that I'm dating someone even though I'm still in high school? Tomoko: I'd only object if you were in third-year and studying for the final exams. Since you're a freshman, I think it's alright...As long your grades don't drop and you don't get her pregnant! Josuke: Y-yes, Mom!
Onodera having a strawberry motif on her uniform, including the costume she gets handed by Miyazaki during Josuke's birthday, predates Joshu calling Yasuho Hirose "Little Strawberry" at one point in JoJolion.
In chapter 22, when Fubuki asks about why Rohan kept moving to Morioh a secret, Rohan's response basically predates Episode #10 of Thus Spoke Kishibe Rohan.
Fubuki: Why keep it a secret that you've moved here? Rohan: That's a simple question to answer. Lately, there's been a lot of crazy people among my readers. If word gets out where I live, I'll probably have one or two stalkers breaking into my house.
Tohru Miyazaki being revealed as the werewolf and second Big Bad predates and shares coincidental similarities with JoJolion'sBig Bad: Toru, making for one of the wildest examples considering their similar names and that Miyazaki was introduced well before Toru himself was fully introduced. The following essentially make Miyazaki a retroactive counterpart to Toru. This hasn't gone unnoticed by the author, as Miyazaki's pose in his Stand stat card after The Reveal is a mirrored version of a pose Toru did himself◊.
Both characters are Hidden Villains (albeit executed differently, as unlike Toru, the werewolf is foreshadowed in one of the earliest chapters), and they're even exes of a Rose-Haired Sweetie within the cast.
Furthermore (while a looser example), both of their Stands coincidentally end up fighting the heroes alone for a moment, complete with them being able to speak independently of their users. However, in Miyazaki's case, Bad Moon Rising was not able to do so until Miyazaki's implied Sanity Slippage, while Wonder of U seemed to always have had that trait.
In chapter 39, after having her ear pulled by Fubuki upon learning Aya's a Stand user, Ichikawa asks him how would he like it if his ear got pulled on. One sequel later, that would actually happen courtesy of Hitomi, with Josuke lampshading how it's Laser-Guided Karma.
During the When Doves Cry arc, Josuke encounters a water clone of Dio, which manifested from Jotaro's memories since he got exposed to the storm a second time. This predates a chapter of Crazy Diamond's Demonic Heartbreak about two years later, as Josuke would come face to face with a memory of Dio as he and Boingo get trapped by Pet Sounds' Stand.
In this story, Yoshikage Kira kills Yasuho Onodera, and while he looks at her hand sometime before doing so, he ultimately doesn't take it. Come the release of Wonder of U (who also has Toru speak for intro and victory animations) in JoJo's Bizarre Adventure: All Star Battle R, Toru's victory quote against Kira has Toru remark on if Kira were to go after the hand of Yasuho Hirose (who Onodera is an Expy of) as another reason to kill him. As a result, knowing about the fanfic's events can make this part of the interaction pretty funny, since Kira did something similar to a Yasuho.
Fridge Brilliance: When Onodera's Alternate Self appears to Josuke's shock at the end of chapter 1, she's immediately characterized differently than her water clone from the main story, as one trait of how Onodera normally acts is seen right off the bat, even if she is annoyed. She then just reminds Josuke about their planned date as she pulls his hand. It's a small thing that also helps tell the reader that Josuke isn't in any danger this time with this Onodera, considering he nearly died the last time he saw her Back from the Dead.
Upon the reveal that Josuke and Fubuki are in another timeline where the main events of the story never happened thanks to the arrow Keicho stole never being in Morioh, Kira and Miyazaki being alive means they continued to kill women and children uncontested for nearly all of 1999. This gets addressed in Chapter 3 by the mission to sneak into Kira's house, and Rohan looking into Miyazaki with Heaven's Door. Upon doing so, he's horrified by his discovery, since Fubuki didn't go into the details on why he also wanted Miyazaki arrested.
There's also the possibility that Katsumi Hamano is still alive too, possibly still using her Stand to kidnap girls and sell them on the Black Market. Considering Higura's nowhere to be seen so far, and that Katsumi forced her into doing her bidding originally, she could have done so in the alternate timeline too, uncontested just like the other two killers.
Fridge Sadness: The alternate timeline being one where the main story's events never happened most likely means that Jotaro and Hitomi never reconnected in this timeline, which can get pretty sad to think about when you remember that before the main story's events, Hitomi had been bearing the emotional burden of what happened in Italy and her father's death, and she tried to call Jotaro numerous times, but received no answer.
In the main story, Rohan considered using Heaven's Door on Miyazaki, who was later revealed to be the werewolf, which is Dramatic Irony on a re-read as noted above. Here, Rohan's Alternate Self actually gets to do it, but out of curiosity for why Fubuki said he should be arrested, which also doubles as a clever use of a "What if" scenario in a story set in an alternate timeline.
While there being an Alternate Self for Rohan Kishibe is naturally because of an alternate timeline, The JOJOLands would later involve a literal alternate Rohan that exists in the same continuity of Steel Ball Run, complete with the same Stand.
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