The Running Gag of Musashi saying something in English and having to immediately clarify herself since none of her allies understand or even recognize English.
When Saber invites themselves into Iori's house after Rider wrecks it, an exasperated Iori has to explain that the house is usually tidier.
Upon meeting Saber for the first time, Kaya Squees over the fact a cute girl is staying at Iori's house before promptly asking Saber about when they're planning on holding their marriage ceremony.
Saber becomes enamored with seeing all the sights in Okachimachi and runs off on their own. By the time Iori catches up and chastises them for playing around when they're on a mission, Saber refutes they're not playing around while wearing a festival mask on the side of their head. They then quickly proclaim they were just blending in with the locals. Even better, going back to Iori's house after this point will occasionally have Saber wearing the mask while at rest.
While trying to catch a calico cat for its owner, Saber decides to use their Servant intangibility to catch it while it's fleeing. By the time Iori catches up, he finds a triumphant Saber... and a dog.
When Iori and Saber explores Chiemon's recently deserted camp at Koishikawa, they mainly find journal entries from him detailing serious things about him like the Shimabara Rebellion. Located near these entries is a weird note written in much girlier speech from the not-yet-introduced Circe warning the reader of the note not to snoop around the camp, which sounds nothing like how Chiemon or Lancer acts.
Rogue Berserker's final Digression starts with Iori and Saber encountering Musashi who explains that Rogue Berserker disappeared from Yoshiwara suddenly. They find him sitting curled up outside of Iori's house with his knees in front of his chest and Musashi promptly berates him like a child getting lost. Keep in mind Rogue Berserker is a giant man and even while sitting he's still nearly the height of the standing Musashi.
Musashi: Didn't I tell you not to run off like that? It's not easy chasing after you.
One of Cu's Digressions has him show up in Asakusa to pursue the presence of what Iori believes to be a fearsome monster. After following Cu around town, Iori discovers that the presence Cu sensed was actually Gilgamesh and the two of them instantly starts a spat due to their pastencounterswitheachother which Iori is totally clueless about.
One of Gilgamesh's Digressions takes Iori to Akasaka, where he alongside Zheng and Archer attempt to try and guess Gilgamesh's True Name. Archer rattles off all the qualities he doesn't like about Gilgamesh such as his arrogance and condescending demeanor before questioning if Gilgamesh is actually Cao Cao.
During Musashi's Digression in Shinagawa where she follows Iori and Saber to do some shopping, going out of your way to speak to the headsman will have him make an assumption and remark on Iori being popular with the ladies.
Sukenoshin is a Plucky Comic Relief whenever he appears and his actions range from shipping Iori with Saber due to misinterpreting their relationship to showing off towards a woman in Yoshiwara by attempting to fight a monster attacking the town only to run away once Iori and Saber shows up to offer their aid.
Circe feeds Iori some kykeon, with the expected results. Saber is shocked that Iori is turned into a pig and eventually starts teasing him like a pet by calling him cute.
Later on, Circe turns the Crimson Codex into a pig too, with the partial results being a flying book with a large pig nose who can still talk but now unwillingly peppers his speech with pig verbal tics. Gramps promptly freaks out and begs Iori to help restore him to normal while Saber laughs at his expense. Even after the transformation is reversed, you can still find an entry in the Logbook written by Circe in the first person as a reminder of the ordeal.
The first time Saber helps Iori jump up a high cliff, Iori isn't very pleased with Saber's method of doing so.
When Iori is turned into a pig under the influence of Circe's kykeon, Saber just throws him up with both hands instead and pig Iori will squeal in fear while flipping through the air before angrily oinking once he lands and Saber materializes at the top.
Circe's Noble Phantasm is identical to the version seen in Fate/Grand Order, so it can be jarring to compare everyone else's Noble Phantasms to her relatively sillier looking one where she summons a hoard of cartoonish pigs that stampede towards a feast.
Foreshadowing for what's actually going on with Iori aside, Gilgamesh's Joke Ending would be hilarious on its own with him successfully tempting the protagonist to join his new campaign to conquer the world - strong-arming Saber in the process - but the credits that follow solely feature the three of them and their voice actors. That's it.
When they finally find themselves in front of the Waxing Moon Vessel, Saber asks Iori how they should dismantle it. Exhausted, Iori brusquely suggests that they just cut it to pieces since that's how they've dealt with most of their problems during the ritual. Saber initially nods before backtracking and realizing what a dangerous idea that is; citing that it might release the spirits of their enemies that are currently powering it. The Crimson Codex chimes in, and assures the duo that would never happen. Rather, if they slash it, the vessel will violently explode and destroy all of Edo.
Record's Fragment: Keian Command Championship
Just the fact the DLC starts simply because Boss was bored and decided to use his authority as Ruler to change how the Waxing Moon Ritual will be fought... by turning it into a spectator tournament. Sure, there is other stuff going on behind the scenes, but this is definitely something a bored Gilgamesh would do. Even better, his bio entry for the DLC states that there were other methods of sealing Ibuki-Douji available, but went with the Keian Command Championship simply because it's the one that brings him the most amusement.
At the start of Musashi's route, Rogue Berserker heads off to find the golden statue on his own and repeatedly finds the wrong items - at one point even staring at a cute puppy with a golden coat and responding with innocent confusion when Musashi tells him the puppy isn't what they're looking for.
Due to Dayu not being around to lead them, both Musashi and Rogue Berserker get easily distracted by things like eating udon, with Boss having to chime in to remind them to continue the treasure hunt so they don't forfeit the match. Rogue Berserker actually seems to be more excited for the udon than Musashi herself, as he runs ahead and sits in front of the stall with his knees up.
The fact that almost everyone aside from Boss and Tsuchimikado still want to get back to the Waxing Moon Ritual, not realizing that the Holy Grail (which many characters refrain from naming) isn't a Shoddy Knockoff Product of the Waxing Moon, but rather the reverse. Tsuchimikado is the only outlier because he knew about the Holy Grail from the beginning and based the Waxing Moon off of it simply because he wanted a grail he could control.
Dorothea and Assassin have some pretty good moments in their route:
During the first round with the golden statue treasure hunt, they're treated to the sight of Musashi and Rogue Berserker running all over Yoshiwara loudly shouting about their search. Dorothea after a moment's silence decides they'll go with their own more discreet approach.
Their ending addresses a long-standing problem that mage families tend to have: money. Dorothea takes a page out of Marisbury Animusphere's book and uses the Holy Grail to basically wish for funding, and since her mage family's prosperity was what she set out to achieve in the first place, she completely blows off the Waxing Moon Ritual and spends her time going on treasure hunts with her crew and Assassin (who has now donned a pirate hat).
Due to their connection through his snake curse, when they meet Ibuki-Douji Assassin tries to be respectful and deferential towards her, calling her "Elder Sister"...and Ibuki-Douji is having none of it. She proceeds to spend nearly half of her introduction in this route acting like an embarrassingly affectionate older sister, insisting that Assassin calls her "Big Sis" (Onee-chan) and constantly referring to the tall, dark and menacing servant as Sabu (Sabu-chan). Assassin can barely do more lower than his head in bewilderment and damn near begs her to stop.
Lancer's route has Circe showing up to cheer on Chiemon and Lancer in the stands. Chiemon is befuddled at her presence and quickly denies all her attempts to get him to eat her kykeon.
Everything about Ibuki-Douji. Especially when Tsuchimikado is involved. His dignity may never recover.
Her first appearance is her playing up the "I'm a Serious Goddess Threat that could be unleashed on the world" angle that even got Boss to respond... for all of 10 seconds before she drops the act and behaves like the doting big sister seen in Chaldea.
Summoning Ibuki-Douji was Tsuchimikado's plan from the very beginning. The whole reason he summoned Caster was abuse his Reality Warper powers to make it happen, before Caster and even Boss shut it down. The DLC's origin point is if Tsuchimikado refused to give up and forced the summon with the Waxing Moon, adamant that he can command the Ruler Servant... only to learn the hard way that Rulers can't be controlled, because the whole point of the Class is to prevent exactly the sort of trouble Tsuchimikado is trying to cause. Ibuki-Douji promptly runs off to do whatever she wants, forcing Boss to clean up the mess, and every attempt Tsuchimikado makes to regain control of the situation is utterly useless.
Caster: Though my predictions show you at the end, whining "how did things turn out this way"? Tsuchimikado: Hmph... just you watch. (cuts to the present day) Tsuchimikado:How did things turn out this way...? Caster: And so my prediction comes to fruition. Are you not astonished, Tsuchimikado?
Caster in general in this episode is utterly hilarious, by constantly tossing shade at Tsuchimikado's incompetence and mocking his way too grand ambitions every time.
By extension of the above, the entire DLC plot can be summed up as: "Tsuchimikado got too big for his britches. Ibuki-Douji brought his ego back down to Earth."
Want to see a perfect demonstration of how Yasuhiro and his brother Takatoshi are like night and day? While Yasuhiro is left utterly exasperated by Ibuki-Douji, Takatoshi actually likes her and is happy to do things like cheer her on in the tournament. Even Ibuki is surprised and calls him a charmer.
Takatoshi: I must say, it feels almost too quiet now that she's gone. Yasuhiro: Yes, well... Actually, no! I like the quiet; I'm glad she went back. I'm never calling her again!
Tsuchimikado and Caster's ending. Ibuki-Douji "accidentally" uses the Holy Grail's leftover energy to let herself stay manifested. Not only does this use up Tsuchimikado's wish before he can cast it, but she shacks up with him under the pretense that she'll help him win the Waxing Moon Ritual... except she has no concept of subtlety and wanders around in her snake form in full view of everyone, playing merry hell with the longevity of mystics and generally ruining Tsuchimikado's schemes just by existing. Be Careful What You Wish For...
Even better, his brother Takatoshi takes all of this in stride and is fine carrying her shopping bags around, going so far as to state that's just what friends do.
As one last personal jab at Tsuchimikado's dignity, or whatever was left of it at that point, when Ibuki-Douji beats Boss in the final round of the tournament, he proudly proclaims that "The winners are...IBUKI-DOUJI! Oh, and her two attendants." Since all he and Caster really did was cheer her on.
, with the expected results. Saber is shocked that Iori is turned into a pig and eventually starts teasing him like a pet by calling him cute.