The hero is the antagonist, a Smug Super, Jerk Jock womanizer who believes that, because he is superpowerful, he's better than everyone else and is only too happy to display it. He further believes that only people who are like him can be heroic, and anyone who's nerdy or unpopular is a potential supervillain. It's strongly implied that this behavior is what drives people like the villain to become evil in the first place.
The Love Interest is a genuinely good person whom the villain wishes to impress with his evil deeds, failing to realize that she's very unlikely to actually respect that. She gets caught in the crossfire between the two, ends up ignored as they fight their climactic battle over her, and dies tragically as a result.
This website deconstructs the Cthulhu Mythos, specifically the Necronomicon. In essense it asks "what if it was a real book?" and builds from there, by looking for paralels between Judeo-Christian tradition and the Cthulhu Mythos (The Old Ones = The Giants from Genesis), it creates the content of the book, it then asks "what kind of person would write about such things in 730 AD?", thus Abdul Alhazred is what the Koran calls a "Sabian" and what western biblical scholars call a "Gnostic" a person with religous views related too, but radically different from mainstream Christianity, Islam and Judaism. It then builds a comprehesive history of how it got from the middle east and into the hands of western Occultists, and finally makes the assumption that while, yes Lovecraft wrote about it, he got only the name and the the author correct, having never read the book itself.
Stardestroyer.net, as mentioned above in Fan Fic, deconstructs the seemingly utopian Star Trek universe, pointing out holes.
Sailor Nothing loves showing just how jarringly, horrifically, nightmarishly different the characters' lives are from Magical Girl anime. Several of them even watch an exaggerated, stereotypical version of such shows; the main character actually watches it to escape her life.
Red vs. Blue: The Blood Gulch Chronicles takes many first person shooter tropes and twists them. Everything from capture the flag, to why there are two bases in the middle of a box canyon with no strategic value, and Respawn. Interestingly, the new series called Reconstruction is a deconstruction of the parodic nature of The Blood Gulch Chronicles.Caboose is tied up in the brig due to his self destructive tendencies. Grif and Simmons face the firing squad after selling all the ammo to the Blue team. The reason that all the red and blue conflicts were pointless squabbling over an equally pointless flag and base is revealed to be a conspiracy by command. However, since that is a deconstruction of a deconstruction, arguably that makes it a Reconstruction as all the video game tropes are being put back together.
The SCP Foundation Wiki, although beginning as a Creepypasta site, has largely evolved into a deconstruction of the Urban Fantasy genre, depicting a shadowy organization entirely devoted to capturing and imprisoning all of those magicians, psychics, and mystic artifacts that populate said settings, to maintain the status quo. It is made abundantly clear that this is for humanity's own good.
And by humanity's own good meaning that the fantastical creatures that roam the earth are not only nightmare inducing but can bring fourth the end of the world as we know it. Yet no matter how much effort the organization put in containing such creatures/artifacts the end result is tragically inevitable.
Furry Fandom works frequently portray an entire world as furry. I Wish I Was Furry! shows what would happen if we woke up one day and the world actually was furry. The main character is even a human furry fan, like is typical for transformation stories. And a plushophile. (It's exactly what it sounds like.) A furryized world, as it happens, is dark and brutal. "Nature, red in tooth and claw" and all that.
This video from The Onion sends up the idea of video games becoming progressively more realistic by taking it to a logically deconstructive extreme with a "ultra realistic Call of Duty: Modern Warfare 3". It mostly involves sitting around and waiting.
The Whateley Universe is a deceonstruction of the classic superhero/supervillain tropes, with mutants who have to obey real physical laws, some supervillains like Dr. Diabolik who are pretty far from the classic villain, and even some supers who are far from the classic hero.
This video is a deconstruction of Pokémon. Yes, Pokémon. It is mostly played for laughs but there is a point about half-way through where Pikachu is bleeding as he's strangled by a Bulbasaur and it's played straight.
The Sex House series does this quite brutally to Immoral Reality Shows. Not only are the contestants much deeper and complex people than the shallow stereotypes the show desperately try to portray them as, the producers' "indicatives" to cut corners on the budget and ensure sex and drama in order to get the precious high ratings rolling in, soon starts to take a massive toll on their sanity and health.
The Salvation War: A destruction of Biblical apocalypse. The apocalypse is resisted by most of humanity, with only a minority choosing to accept the end. The unstoppable Demon hoards, while individually physically more powerful than the average human, are annihilated by modern weapons, and their extreme evil and backwardness means cooperation and experimentation hamper them constantly. Angels are hardly better off, their only major advantage being their ability to keep humanity out of Heaven. But they soon lose that advantage, and God is brought down by an angel himself. The seven bowls are damaging at a societal scale, but not enough to completely annihilate civilization. Heaven itself is not-so-wonderful, due to the medieval mindset of most angels meaning it only provides what was considered plentiful in a medieval society: crops, shelter, and protection from bandits, but it contains none of the technologies or political ideals that modern people enjoy.
We'll Meet Again is a long-running alternate timeline on AlternateHistory.com. The story was intended as a backlash to all the timelines littering the site where the American Revolutionary War either failed or never happened and America stayed in the British Empire, and everything is rosy because of it. In this the timeline diverges visibly within a few years of the POD, and enormously by the turn of the 18th century, and here, it isn't rosy. Notatall.
Another story on AlternateHistory.com, Decades of Darkness, was written as an attempt to make a more realistic version of S.M. Stirling's Draka series, which the author saw as wildly implausible in how its evil, mass-enslaving South African empire is able to conquer the world while everybody else clings tight to the Idiot Ball until it is too late. In this version, instead of South Africa, it's the United States that becomes The Empire after a disastrous loss in the War of 1812 that sees New England and New York secede and British Canada claim a large swath of the Midwest, leaving a rump nation that is dominated by the planter aristocrats of the Deep South. This national humiliation leads to the rise of a proto-fascist, white supremacist ideology that justifies conquering 'lesser' peoples in Latin America as putting them in their 'rightful place', with a string of highly competent leaders able to put this plan into practice. The British Empire tries to check their expansion spree, though it does little good in the end. By 1933, the US is the master of the Western Hemisphere and starting to extend its tendrils into Africa, the only independent nations left in the Americas having all been hopelessly Finlandized. Everybody in the world is fully aware of how evil they are, and the fact that they couldn't put aside their petty differences in order to stop this monstrosity, instead letting the Americans consolidate their brutal rule in South America while they were distracted slugging it out in the Great War, is regarded as a tragedy of biblical proportions.
During the ITTL 1970s, the two party system slowly shatters. But rather than leading to more efficient, responsive government, it leads to political chaos, as the political system has not been reformed to deal with the change. Due to a third party runs by George McGovern and George Wallace, the 1972 election results in there being no winner in the Electoral College, leading to a political clusterfuck that allows Spiro Agnew to slither into office. As the political and economic problems of the 1970s persist, new political parties form, but they create further confusion, since the winner take all system turns them into spoilers that result in unexpected and unwanted results: Spiro Agnew, for example, becomes Mayor of New York because of the divisions between left wing parties, and Harvey Johnson, a liberal black man, is able to become a Mississippi Senator due to a division between right wing forces. In 1980, Donald Rumsfeld, without winning the most popular votes, manages to win the Electoral College due to this same political division between Democrats and the left-wing We The People. In 1984, he is able use this same division to get away with rigging the election and drive the Democrats into the ground.
ITTL, the US is able to win the Vietnam War, that is to say, secure South Vietnam's independence. While this does to lead to celebration, it results in the US government, secure in the idea of foreign intervention, adopting a more bellicose and interventionist foreign policy. By the 1980s, the US is expending resources and lives invading and propping up anti-communist regimes, and Donald Rumsfeld's anticommunist drive is so lunatic, he alienates Western Europeans who want detente with the USSR, leading to the collapse of NATO.
Per Word of God, the sequel is largely a Deconstruction of Tea Party conservative social and economic ideas being put into place, vs. what the kind of president Ronald Reagan. During the 1980s, these policies turn America into an authoritarian hellhole under the presidency of Donald Rumsfeld. By the tail end of his term, his deregulation of the economy is so severe, the corporate figures that backed him support his impeachment.
This video by The Racka Racka does this with the "prank war" genre of YouTube prank videos, with a father and his sons carrying out an Escalating War of pranks that starts out harmless but very quickly turns dangerous. Eventually, the father gets badly maimed and kills his sons and wife as a result — and one of the sons still thinks it's a prank even after his dad has started shooting while wearing a creepy pig mask.