These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
British people: Buffy calls Merrick a "scone-head."
Accidental Innuendo: "I was just saving your butt!....Well, there was an exchange of butts...."
Adaptation Displacement: Some fans of the series probably weren't even aware that a movie was made.
Few have seen the movie. Whedon considers his script — not the film that was actually made — to be canon.
Big Lipped Alligator Moment: In the school counselor's office, Buffy kills a fly by spitting a dart at it - apparently for no other reason than because she's bored.
Complete Monster: Just how incredibly evil is Lothos, Buffy's vampiric arch-nemesis? He is shown at one point preparing to have a cute little kitten for supper....while it's still alive.
Retroactive Recognition: Hilary Swank as Kimberley, one of Buffy's Girl Posse. Ben Affleck and Ricki Lake in bit parts, as a baseball player and a waitress respectively. Though his scene got left on the cutting room floor, Seth Green (Oz from the series) does appear on the tape, and DVD covers.
Seinfeld Is Unfunny: This movie bombed in its theatrical release but proved to be a cult favorite on videotape. It was this cult status that ultimately inspired the TV series, which ironically now tends to make the movie look bad by comparison.
Alas, Poor Villain: Ampata from "Inca Mummy Girl", in-universe and out of it.
Alternate Character Interpretation: Or rather, Alternate Episode Interpretation. The much maligned "Beer Bad" is actually a really funny and enjoyable episode if you approach it as just an amusing story than an anvilicious lecture.
Anvilicious: Willow's storyline in Season 6 (drug addiction) "Beer Bad" (alcoholism), "Pangs" (atrocities to Native Americans), "Halloween" (female empowerment).
While pants-soilingly disturbing, the most heavy-handed part of "Gingerbread" ( about prejudice) was when Cordelia fire hosed down the brainwashed parents.
Angst Dissonance: Buffy in season 6. Yes, it must have been absolutely terrible to be ripped out of heaven into earth, which can really suck, but after hearing Buffy complain about it for the entire season gets really grating. She still has a good life, despite having the burden of being a slayer. Of course, in real life it would take a long time to be able to get over such an ordeal, but fiction, especially television, is allowed to speed up grieving as so not make the viewer want to smack Buffy in the face to get her to shut up.
Badass Decay: Formerly known as Spikeification, as Spike went from an intimdating presence who was cool in his evil-doing and clever enough to fool Angelus, to a sort of Butt Monkey who lost most of his cool, and nearly all of his evil and cleverness. He got over it by Season 7, and completely inverted it when he moved to LA afterwards.
It's the price that had to be paid for keeping Spike around. S2 & S3 Spike was established as such a badass, that Buffy could never have a conceiveable excuse for not dusting him if she got the opportunity to, and badass Spike, would of course kill Buffy if he could. The two could only co-exist if Spike was rendered to be a non-threat, such as the chip he gets in S4. Of course a harmless Spike is anything but a Badass — and the Scooby gang never tire of reminding Spike of this in S4.
Big Lipped Alligator Moment: After the opening theme rolls in the episode "The Body" we see a five minute random flashback to Christmas dinner at Buffy's house that has nothing to do with the rest of the episode. Word Of God has said the scene is there because they didn't want to have the opening credits playing over Buffy trying to revive Joyce.
The Men in Black subplot of "Out of Mind, Out of Sight" which was never brought up or mentioned again, not even when the Initiative showed up or when the army went against the Slayers in Season 8.
Angelus, very thoroughly. And probably Caleb. And Warren Mears after trying to rape, and successfully killing, Katrina.
Adam, depending on whether having been built to be a killer excuses him. Also - The First Evil, obviously.
Various other one-shot villains who may qualify:
Catherine Madison, Amy's mother. Drives her husband away out of fear of her magic, constantly abuses her daughter, steals her daughter's body when she disapproves of Amy's life choices, casts potentially fatal spells on innocents just to get her way (one which would have been fatal), and to top things off, tries to trap her own daughter in an inanimate cheerleading trophy for eternity out ofspite!
Zachary Kralik, insane vampire with Mommy Issues who kidnaps and torments Joyce to lure Buffy in. At a point in the series when vampires were more or less Mooks he manages to be genuinely threatening on the basis of nothing but his own utter hideousness.
Der Kinderstod, a Freddy Kruger-esque demon who's murdered children in the sleep For the Evulz, including Buffy's own cousin.
The monster from "Gingerbread" who hypnotized the parents of Sunnydale to kill the local witch population (ie, their own children).
For a more mundane example, the Little League coach who abused his players, beating one so severely that the kid ended up in a potentially fatal coma.
Designated Protagonist Syndrome: It's arguable, but there are quite a lot of fans who don't especially care for Buffy herself. Especially in the last season, when she starts giving those "I'm-better-than-all-of-you-and-you're-all-gonna-die" inspirational speeches.
Draco in Leather Pants: Spike is a standout example. His eligibility for such an appearance is increased by his very obvious (and, unfortunately, entirely canon) Badass Decay.
Faith. Those pants are personally responsible for some sympathetic views of Faith in fanfic. And lots of Freudian Excuse, a well executed Heel Realization and Heel Face Turn works to excuse... well, most of her acts. And Shipping of course, mostly Buffy/Faith.
Dude, Not Funny!: When Buffy uses her invisibility to make a social worker look insane and get the case file on her and her sister ignored. Apart from Buffy actually being an unfit guardian, the social worker could get fired.
While Buffy is honestly an awful guardian Willow (and Tara, before she left) more than made up for it. Besides, the social worker can't account for all the stuff she doesn't know like Spike's blanket being for an anti-death purpose or the fact that, honestly, Dawn's grades don't matter. It's really impossible to get out of the whole Slayer stuff, as she proves in Season 8. Plus, the planet owes them one for saving it repeatedly.
Ensemble Darkhorse: Spike. It's clear that he was a major character from the get go (but originally just for Season 2), and the writers always liked the character, but it seems like nobody quite expected just how mucheveryone was going to love him. Many, many Buffy fans consider him the best character in the show, to the point where despite the weirdness of his relationship with Buffy in Season 6 there are still a vast number of Spike/Buffy shippers about.
Fan Dumb / Hate Dumb: It's not as obvious nowadays, but when it was airing, complaining about Buffy was one of the two things the internet did. The other was gushing over it.
Buffy/Angel and Buffy/Spike battle for prominence among the fandom, generally depending on which season(s) the particular fan prefers.
Fetish Retardant: Vamp!Willow, who not only looks like an old hag is utterly psycho. Faith, when she goes bad it overshadows anything that was appealing to her, though in this case it's deliberate.
Foe Yay: Buffy and Spike (which later becomes Dating Catwoman), Buffy and Faith, the torture scene with Drusilla and Angel in season 2, Drusilla and Kendra, Giles and Ethan, Glory and Dawn, and most famously Xander and Spike.
Foreshadowing: Word Of God says they hadn't planned to make Willow gay as of The Wish let alone even earlier in Phases, but then there's this exchange:
GermansLoveDavidHasselhoff: The show was successful in the US but enjoys massive popularity in Europe, where the stigma of science fiction/fantasy isn't as pronounced.
Of course, now Chiller, Oxygen, Logo, and Teen Nick are all showing it in the 'States.
Growing the Beard: Starting with the arrival of Spike and Drusilla. Full growth was achieved when Angel lost his soul.
Harsher in Hindsight: In Season 4 Buffy and Faith switch bodies, with the former appearing a complete and total Jerkass and the latter desperately trying to gain acceptance. Compare and contrast season 7.
Also, in Season 2's "Halloween", Spike is about to kill Buffy, who is weak due to taking on the personality of a colonial-era proper lady. The comment Spike makes about her and her situation before he makes the attempt sounds alot like he's about to rape her. Way later, there's the infamous incident in Season 6.....
Although no viewer could have known it at the time, the whole plot where if Angel experienced one moment of true happiness, he would lose his soul turns out to be a pretty good metaphor for any fan of anything Joss Whedon has written since ever. (Although most of us tend to be more "constantly depressed" than "irredeemably evil.")
Spike: You wanna put these demons down and end this Twilight crap once and for all?
Another Twilight example comes from the first season when Angel is in Buffy's room (It Makes Sense in Context) he mentions how great she would look when she sleeps. It gets even better when all he does is sleep on her floor.
Twilight is so RICH for this. The first episode of Season 2 has Buffy telling Angel that girls don't think stalking is sexy. Apparently, Buffy is very atypical.
The episode Nightmares, when Willow says they're facing their dreams. Giles corrects her that it's nightmares. "Dreams would be a musical comedy version of this." This of course gets a Shout Out in Once More With Feeling, when Willow sings "I've got a theory, some kid is dreaming, and we're all trapped inside his whacky broadway nightmare."
Ho Yay: Buffy and Faith, Drusilla and Kendra, Vamp Xander and Angel, Glory and Dawn, Xander and Spike so ''so'' much.
Olaf: YOU DO WELL TO FLEE, TOWNSPEOPLE! I WILL PILLAGE YOUR LANDS AND DWELLINGS! I WILL BURN YOUR CROPS AND MAKE MERRY WITH YOUR MORE ATTRACTIVE DAUGHTERS! HA HA HA! MARK MY WORDS! (Pauses and sniffs the air) OOH! ALE! I SMELL DELICIOUS ALE!.
There was also Balthazar the fat demon, and the original Big Bad, the Master.
Les Yay: Willow and Tara, before their relationship became explicitly romantic. According to Alyson, Joss worked very carefully to create the right subtext in their scenes together. Creators have also acknowledged lesbian subtext between Buffy and Faith and say in the commentary that it was fun to play with.
Sweet from Once More With Feeling. He came to town, killed a bunch of people, made the Scoobies reveal a bunch of embarrassing secrets about themselves, nearly killed Buffy and left town without getting a scratch on him. Enough said.
Memetic Badass: Buffy's plan in season 7 involves Spike becoming this. Results vary.
Buffy: They're trapped in here. Terrified. Meat for the beast, and there's nothing they can do but wait. That's all they've been doing for days. Waiting to be picked off. Having nightmares about monsters that can't be killed. But I don't believe in that. I always find a way. I'm the thing that monsters have nightmares about. And right now, you and me are gonna show 'em why. It's time. Welcome to Thunderdome.
Also, in a more unusual example, Xander. By any Real Life standards, Xander is Badass simply by merit of the fact that he's still alive after seven years of fighting the Good Fight (or more, depending on whether you count the Season 8 comics as canon). In many a Fan Fic, this is taken Up to Eleven, and Xander effectively becomes the merciless god of his universe.
D'Hoffryn in "Selfless" after he kills Anya's best friend when she was expecting to be able to sacrifice herself to bring the people she killed back to life. He was more of an Affably Evil guy before.
This moment is made especially disturbing by his casual comment that "he has plenty of girls", making him sound less like an amusing albeit demonic office boss and more like a pimp.
The Trio were just considered a nuisance until Warren accidentally killed his ex Katrina and made Buffy think she did it. Then, there was "Normal Again"...
"Family": "Tara, if you don't get in that car I swear by God I'm gonna beat you down."
Nightmare Fuel: While most of the things that take place in the universe are pretty creepy and disturbing with a hint of dark humor, Skinless Warren in the comics will haunt you, even if he does still have the same dorky ass persona from before.
One True Pairing: Angel and Buffy. While both date other people and fall in love with other people, in the end it always comes back to their tragic and doomed relationship, to the point of them eventually planning to be together when Buffy is ready/when Angel becomes human. Also to the point that it can become extremely annoying.
Joss' policy was always "bring your own subtext," and he never really had any pairings set in stone. Sarah Michelle Gellar still thinks that Buffy and Xander were supposed to end up together.
Rescued from the Scrappy Heap: When Tara was first picked as Willow's Suddenly Sexuality love interest, fans wrote such viciously nasty things about her all over the net that Amber Benson nearly left the show. Fast forward to her death two seasons later, and Joss Whedon actually received death threats for letting her go.
Willow was a Scrappy Generator. Oz started out as a scrappy because he wasn't Xander. Tara started out as a scrappy because she wasn't Oz. Kennedy was a scrappy because she wasn't Tara.
Basically everyone is The Scrappy to someone. Especially Buffy herself, mainly in the show's later seasons.
Take That, Scrappy!: Willow reams out Dawn for being a whiny crybaby in "Two To Go". And in the comics, she breaks up with Kennedy.
There was also when Buffy snarked about Dawn's position as a Damsel Scrappy.
Seasonal Rot: Seasons 4, 6, and 7 are the least-regarded seasons of the series.
Values Dissonance: Villains is full of it. After the things Warren does, including nearly killing Buffy, he comes back, shoots Buffy and kills Tara. Apparently Willow wanting to kill him for these things is wrong, with Buffy about the only one not going for it.
Because Willow was trying to murder for revenge - justice had nothing to do with it. While Warren is an asshole (at least after his actions to this point), the episode posits that killing for revenge, while not without reason, is objectively wrong. More to the point, killing him didn't make her feel any better in the long run and only drove her further down the path of evil - whether or not Warren deserved it, Andrew and Jonathan didn't.
Demonic Spiders: Actual demonic spiders at that. They're quick, knock Buffy down in one hit (intsakill on low health) and can not be punched.
Genius Bonus. In a bid to be resurrected, The Master possesses Angel. In the first episode of season two The Master was not played by Mark Medcraft, but David Boreanaz.
Good Bad Bugs: When certain enemies are killing Buffy it's easy to go to the inventory and heal.
Les Yay: Willow keeps referring to Tara as sweetie, and makes comment on playing doctors and nurses with her. As an alternate world vampire, Tara says Willow is a domme.
Most Wonderful Sound: Fill up the combo bar and the main theme will sound signalling your accomplishment.
The Problem with Licensed Games: Strongly averted in the first game, which nails the right tone of when the story's set and hits all the right notes. The second game is roughly on par with season six. The Game Boy versions on the other hand follow the trope to the letter.