While reading the other girls' poems, the music transitions to a version using different instruments. Natsuki's version uses a recorder played slightly off-tempo to show how childlike her tastes are.
While Yuri and Natsuki are arguing, Natsuki accuses Yuri of padding her chest ever since the Protagonist started attending the club. Yuri is quick to deny it once the fight settles down, later leading to the player character completely misunderstanding what Yuri didn't want to say was causing her back problems...
In a bit of fridge funny, Natsuki's claim that Yuri's boobs "magically grew two sizes" when the player joined the club could very well be completely right; since Monika is shown to be able to alter the game, it’s entirely possible that she gave Yuri's boobs an "update" upon the player character’s arrival.
During Act 1, the player can call on Sayori for help, which leads to her saying how everyone in the club is amazing at writing poems in their own way, and...
Sayori: Also! Natsuki's cute and there's nothing wrong with that! And Yuri's boobs are the same as they always were! Big and beautiful! Natsuki and Yuri:... Protagonist: Sayori... (Sayori stands triumphantly; Monika stands behind her with a bewildered expression)
The darker variant in Act 2 still has a few laughs, like when Natsuki warns Yuri not to "cut herself on that edge."
Natsuki: Oh, my bad... you already do, don't you?
Act 1, Day 2: Sayori "invites" the player character to come with her and buy a snack. The player character immediately sees through her ruse, deducing that she has no money and wants him to buy something for her.
Player Character: If you had enough money, you would have bought a snack before coming to the clubroom. So, either you're not hungry and wanted an excuse to take a walk... or, you planned to conveniently forget that you spent all your money, so that I would lend you some! But there's one more thing... You're always hungry! And so, that only leaves the one option!
Apparently, Yuri found the entire situation amusing, and she tells Sayori that her suffering after getting caught in the act is, in her words, "fair enough retribution". Sayori then proceeds to bungle the word "retribution" and say a similar-sounding word instead.
Sayori: You were right, though... I did something bad and now I have to accept the revolution. Protagonist: Retribution... Sayori: That!
Natsuki, who overheard Sayori admit that she tricked her into making cupcakes so that the player character could come over, then offers Sayori a cookie... by pelting her in the face with it from across the room. She decides that it was worth it for Sayori's reaction.
Sayori: I-Is this a miracle? It's because I paid my restitution! Protagonist: Retribution... Yuri: Actually, that one almost worked... Natsuki: Ahahaha! I was just gonna give it to you, but then I heard you blab about the cupcakes. It was totally worth seeing your reaction, though. Ahaha!
Followed by Sayori giving Natsuki a big hug... then taking a bite out of thechocolate cookie Natsuki was keeping for herself. Even Yurifound it hilarious. However, it’s a bit less cute when you realize Sayori inadvertently ruined Natsuki’s chance at a snack, considering she always has to bake them herself due to neglect (Act 1) or simply never gets the chance (Act 2 onwards).
Shortly afterward, Monika's lateness causes the group to speculate about her having a boyfriend. When Monika arrives, Sayori promptly declares:
The Animesque style of the game is lampshaded when Natsuki tries to make a pun on fried squid and Monika's name that only works in Japanese (The Japanese word for squid is pronounced as "ika", hence "Mon-ika"). Monika points out that that joke "doesn't make sense in translation", even when you're playing in the original language (English).
Even though things have already taken a dark turn by Act 2, it's still sort of hilarious when demure Shrinking Violet Yuri loses her temper and drops a completely unforeseen Precision F-Strike at Natsuki.
Just before the player finds Sayori after she hangs herself in her house, Monika cracks a horribly accurate pun:
Monika: Ahaha. You should take a little responsibility for her, [Protagonist]! I mean, especially after your exchange with her yesterday... You kind of left her hanging this morning, you know?
Additionally, the name of the song that plays during Sayori's death scene is named "Sayo-nara".
Not far into Act 2, the Protagonist walks into the club thankful that everything's normal. Cue◊ Yuri◊.
Bonus points for the protagonist commenting on Yuri's expression when she doesn't have a face. Not a Deadpan Snarker thing (it's implied that he cannot see the glitches), but still.
At some point in late Act 2, a file appears in your game folder simply named "have a nice weekend", which can't be opened and disappears after the scene is over. This counts as Crosses the Line Twice, considering it foreshadows Yuri's suicide and the consequent scene lasting the entire in-game weekend. As to this, it also doubles as Nightmare Fuel. (You have to wonder whether "have a nice weekend" is Monika actually trying to program a nice weekend for the player character and failing spectacularly, considering that she seems shocked that she accidentally left the player staring at Yuri's corpse for the entire weekend while glitched text displays on the screen.)
In a dark, creepy way, the poem mechanic, as seen in Act 3, is this. To be specific, Monika wonders if that particular mechanic still works, so she tries it out. It does... but just barely. The screen is heavily distorted with black, red, and white coloring, the only sprite visible is Monika, and the only options you can press are various spellings and corruptions of "Monika."
When Monika forces you to try and pick her over Yuri or Natsuki at one point and keeps the cursor sliding toward her name. You can fight it and pick someone else. Sure, you get slight nightmare fuel in the form of the lingering eyes on a blank screen and the game resetting itself, but how it just cuts back to Monika ecstatic over you choosing her is utterly hilarious since you know she rigged it.
Even though it's a rare-chance-of-happening piece of Nightmare Fuel during Act 2, you've got to admit seeing Natsuki's eyes pop out of her head is a little funny just because it's so damn unexpected.
Because you get to personally decide the main character's name and the fact that the textboxes in the game have no visual identification of whoever is actually speaking beyond the name of the character in question, inputting the name of any of the heroines as your protagonist's name will cause quite some confusion whenever said character appears on screen and has a conversation with the protagonist, often to hilarious results that makes it seem like the character is Talking to Themself.
Similar to the above, one scare involves Monika trying to guess your real name by looking at the one on the computer. However, this scare can be funny if the name on the computer isn't actually yours. So, it's possible for Monika to ask if your name is a name of a family member, a pet, what you nicknamed the device, a joke of some kind, or something like "User".
During the practice poem recitations, Natsuki - still very self-conscious about having to read her poem in public - marches to the front of the room and is about to say what her poem is called, when she suddenly has a flustered outburst (which also doubles as Accidental Innuendo for some):
Natsuki: W-Why are you all looking at me?! Monika: Because you're presenting...
Late in Act 2, the player is still writing poems for the girls — and in the final case (not including the glitched one), as the player picks words, they can see the top of Monika's head popping up from the bottom as if to say, "Hey! I'm still here too! Pay attention to me!"
In a Black Comedy sense, Monika's way of making it up to you for unintentionally leaving you locked in the classroom with Yuri's corpse for the entire weekend due to fucking up the game's script is a reassuring smile as she deletes everything else in the game except you, herself, and a room. Before she carries this plan out, she actually takes the time to eat one last cupcake that Natsuki made, complimenting it and saying how much of a pity it is that it would probably be the last time she would be able to eat it. (It should also be noted that her reason for apologizing is that she assumes it was "pretty boring".)
Also in a Black Comedy sense, the sprites of Natsuki screaming and puking upon seeing Yuri's corpse are unintentionally a little funny for how jarringly out of place they are compared to the other sprites. Doubly funny for anyone who plays Yume Nikki, as that sprite is a deliberate nod to the "Vomit-chan" meme from that game.
After you read a poem from Yuri in Act 2, she mentions that her mind has been hyperactive lately, so she decided to take it out on a pen she took from you. When she realizes what she has said, she attempts to clarify, but she ends up making her comment more awkward.
Yuri: My mind has been a little hyperactive lately, so I had to take it out on your pen. Ah— That is... a-a pen fell out of your backpack yesterday, so I took it home for safekeeping and... I, um... I just... really like... the way... that it writes. So I wrote this.. poem... with it. And now you're touching it... Ahaha. I-I'm okay! What did I just... can we pretend this conversation never happened? You can keep the poem, though...
If you consider the yellow stains on the poem Yuri "endowed with her scent" to be her pee, you could say she... Yurinated on it.
In Act 3, it's possible for Monika to discuss the Yandere trope by name and how there was one in the game, which she claims to be Yuri. Monika admits she doesn't understand the appeal, but she "could act scary" if the player wanted her to. She doesn't seem to get the irony.
Monika's Evil Gloating during Act 3 almost feels like a parody of the dangers of villain monologuing, as she not only casually reveals that she deleted the other girls, but proceeds to explain in full detail how she did it. Right down to mentioning there was a file in the game called "characters".note Though it's really because she thinks you're on her side and trusts you not to hurt her, so there. You can practically see the "Eureka!" Moment look forming on the Protagonist's face as you prepare to do exactly that to Monika.
One of Monika's monologues has her Lampshade Hanging her catchphrase "Okay, everyone". She then muses that Natsuki and Yuri might have made fun of her for it. It is understandable that Natsuki would do this, but that Yuri, of all people, would make fun of her for her catchphrase comes off as a surprise, and could be even hilarious.
The Protagonist can help Natsuki get a box of manga from a tall shelf by stabilizing a swivel chair. When Natsuki climbs the chair, the protagonist realizes that he could look up Natsuki's skirt, so he tries to look away. Unfortunately for him, Natsuki notices this and accuses him of setting her up.
The girls gushing over the Protagonist's skills at poetry, considering that in reality they're a mess of randomized words the player picks because they sound like what the girl they want would like when the girls themselves are producing coherent, deep, genuinely good poetry. It's funny when the girls like the Protagonist's poem, and even funnier when they don't - accusing the Protagonist of imitating another girl's style to impress her, which can sound almost like a Stealth Insult considering how nonsensical the player's poems turn out. Monika's reactions are particularly funny, because she approves of anything the player "writes" and makes comments like "I was going 'Ooh!' in my head while reading it", which would sound almost sarcastic if it weren't for how sugary-sweet she is. Especially because she is aware that everything's a game and probably reads your poems as the jumbled mess of words they are.
The player character can doze off while listening to Sayori and Monika discuss what the literature club should do for the festival. Eventually, he will wake up to see Sayori close to his face and get startled. She then rebukes him for staying up late... even though she tends to oversleep.
Sayori: Ehehe, sorry. Wait! Actually, I'm not sorry at all! It's your fault for sleeping like that! This isn't the napping club!
After this, the player character says that Sayori is looking out for others more than she looks out for herself, pointing out how haphazardly she is wearing her school uniform. He then tries to button up her blazer from bottom to top, noticing that it does not fit her properly as he tries to close the button near her chest. Sayori then remarks that it means her boobs got bigger again, embarrassing the player character.
If you uninstall and then reinstall the game in the middle of a session, a text box appears on startup saying that a previous save file already exists. It wouldn't be difficult to imagine that Monika is trying to stop you from undoing all the progress she's made so far.
The game has a habit of getting extremely dark or intense for a moment and then suddenly snapping back to normal, which can be pretty amusing. A great example of this is the scene where Yuri finally gets you alone and badmouths Monika, thinking she's not listening. Her rambling gets more and more unhinged and worrying as Monika fades into the foreground, eventually obscuring her, which is pretty funny in itself despite the intensity of the scene, and then just at the moment you'd expect a jumpscare, the game pops you back into the classroom, where you're asked "Who should I show my poem to first?" as usual.
Meta
One of the opening discretion notes you can get is "PM died for this". Dan Salvato, the game's creator, was also involved in Project M and Melee 20XX, both mods of Super Smash Bros. games. Made Hilarious in Hindsight when one of the consoles the Updated Re-release was announced for was the Nintendo Switch. Funny enough, the line is still present on said version.
Further impacting this is that in Act 3, Monika catches herself talking about Smash, has no idea why she was going to say that, and asks the player to ask her creators why she was going to do that, though note this was taken out in a patch.
Speaking of the opening discretion notes, while a few of them are cryptic or disconcerting, the others... well:
This Game is not suitable for Children and those who are easily disturbed?
This Game is not suitable for Children and those who are easily dismembered
And yes, all of that does imply that in Monika's messing around with the game, she left one message out, got bored and mashed gibberish into the opening screen, and referenced a Wario meme.
A happy accidental one - typing Yuri into Google used to turn up the Wikipedia definition for the Yuri Genre accompanied by a picture of Yuri captioned with "literary genre". What's even better is that the picture of her has changed a few times, ranging from a picture of Monika braiding Yuri's hair to the very creepy in-game sprite of Yuri staring at you with no pupils.
It gets better: in the three preceding pictures, Natsuki is making chocolate, Sayori is wrapping a gift, and Yuri is writing a card. In Monika's picture, she's feeding the player character chocolate from a gift-wrapped box, with a familiar-looking card on the table. It may give the impression that she's taking credit for everyone else's gifts, but a closer look at the card reveals it is signed by all four girls, suggesting they were working on this together. Still, whatever the four girls had agreed to do together for Valentine's Day, it clearly wasn't this.
The physical edition of the updated rerelease comes with Feelies. One of those is a set of standees of chibi versions of the four main characters: Monika forming a hand heart while winking at the viewer, Natsuki doing the classic tsundere gesture of crossing her arms and scowling, Yuri sitting on the ground while drinking tea... and Sayori slipping on a Banana Peel.
transitions to a version using different instruments. Natsuki's version
