Cyberpunk: Edgerunners: David successfully rescues Lucy from Arasaka tower, but is pursued by none other than Adam Smasher himself. After a frantic retreat punctuated by lots of Stuff Blowing Up, they manage to escape by jumping down the side of the tower thanks to David's exoskeleton, seemingly losing him. Lucy even manages to snap David out of his cyberpsychosis on the way down! They reunite with Falco and Rebecca, with Rebecca expressing relief that Lucy is safe, if only for David's sake. Lucy smiles, everything seems like it'll be okay... and then Adam Smasher falls from the sky directly onto Rebecca, with the resulting shot of her mangled corpse revealing that yes, she is extremely dead. Smasher then effortlessly bitchslaps Falco away and knocks off his robotic arm, No Sells Lucy's attempt to quickhack him and burns out her cyberdeck, and then David, who has gone cyberpsycho again following Rebecca's death, proceeds to seemingly fight Smasher on equal footing... for all of a minute or so. Then Smasher effortlessly tears David's exoskeleton apart and proceeds to beat the everloving piss out of him while a cheerful montage recalling David's first time meeting each member of the crew and their resulting gruesome deaths plays to the tune of ''I Really Want To Stay At Your House.''Then David gets his head blown off point blank. Lucy and Falco do manage to escape, but Falco isn't seen again afterwards, and Lucy gets to live out the rest of her days on the moon, completely alone and miserable. The only real consolation is that you get to kill Adam yourself in Cyberpunk 2077.
The Future Trunks arc of Dragon Ball Super. Merged Zamasu has been defeated by the combined power of everyone left on earth, and though most of humanity is dead the remaining people can now work to rebuild the world, hooray! ...And then the sky turns black, getting covered by clouds that have Zamasu's face in them, and it's revealed that every living thing on earth except our heroes are now dead, as the immortal Zamasu is attempting to become the universe itself, and his influence is even bleeding into other timelines, meaning all of existence is at risk. Ultimately, the only solution our heroes can think of is for Goku to ask for help from Omni-King Zeno...who sees the situation, dismisses it as "hideous" and promptly annihilates Trunks's entire timeline. Goku and his friends manage to get back into their time machine and escape back to their own timeline, but Trunks's world is gone forever, meaning that all of his efforts throughout the entire arc were meaningless.
The Fist of the North Star OVA Legend of Kenshiro ends with this. The Big Bad who was thought to be dead turns out to be Crazy-Preparedand in his last breath destroys the city Kenshiro was trying to save. In the final moments of the movie, Kenshiro is the only survivor and can't do much but cry and scream into the ruins. The only thing that saves the ending from complete despair is the sequence that comes after, which has him making his way to a certain village, home to a certain pair of adorable kids and menaced by a certain mohawked scumlord and his army, while "The Road of Lords" plays.
Girls Go Around: The final chapter reveals what has been hinted at, but the full extent can still be quite shocking. The loop created by Chihiro will continue, as Kyousuke's loop on the day of graduation will only end when he kills himself to keep the others safe. There can be no happy ending, with Kyousuke and Chihiro repeatedly going through loops of regret.
Midsummer Chart: The main character of this episode works at a food store and is depicted as a self-centered jerk who gets angry at nearly everything, planning to send people who've aggravated him to hell for petty reasons (including one guy just for dating the girl he was lusting after). He draws violent comics about these people. Mid-episode, he meets a girl who he seems to have chemistry with, and though he starts to draw self-obsessed Wish-Fulfillment comics about her as well, he is shown to actually start caring about someone else's feelings. He enters these comics into a contest and actually wins. On a bike ride home, he notices the girl who lusted after trying to jump off a bridge. In a Heel–Face Turn, he turns back around immediately to try to save her. She tells him her boyfriend played her and three other girls as well. He comforts her and walks her home, afterward he vows to send her ex to Hell for what he did to her and the three other girls, feeling that it's wrong to break a girl's heart. But he can't, because HE is being sent to Hell by the girl who he just saved. She regrets telling him about what happened and fears that he'll tell everyone.
Another episode revolves around a girl about to use the Hell Correspondence to punish an evil old woman who's holding her dogs and the puppies one of them had hostage (and has already killed one of the dogs) in exchange for making the girl her slave. Meanwhile, Hajime tracks her down to try and stop her from doing so. In the end, the police storm the woman's house and arrest her, and it seems like Hajime succeeded...until the girl discovers that the old woman had killed the second dog and all of the puppies, and pulls the string on her curse doll anyway, damning both the old woman and herself to Hell.
Hell Girl does this a lot. Like the first episode of Season 1, the first episode of Season 2 is about a cute school girl getting bullied. Unlike the Season 1 episode, however, the girl or none of her classmates know who's doing the bullying. Her school locker is filled with caterpillars. Her uniform and text books are filled with writing, calling her horrible names. And she is stalked and harassed whenever she is alone in school. A school nurse notices and feels sorry for her. She befriends her and things seem to be looking up. Then a female classmate shows the girl the nurse's office, which is filled with the stuff that was used to bully her. The nurse then reveals herself to be a Psycho Lesbian who is obsessed with her, right down to having a mannequin that looks like the girl. She threats to pour acid on her face, if she doesn't agree to join her in terrorizing other students, starting with the girl who revealed she was the bully. The school girl succeeds in sending the nurse to hell and befriends the girl who exposed the nurse for bullying her, making things seem as though they're going to go better for the school girl after all in a similar vein to how previous episodes ended... until the very last second of the episode before her candle is lit reveals that the girl she befriended had been secretly bullying her as well. Episode over.
Jinrou Game: The protagonist and one other competitor in the "Werewolf Game" manage to survive, singling out that the protagonist's Love Interest was the final werewolf. They celebrate the announcement and it seems like they've won, but they pass out quickly and wake up again in a table, surrounded by new people and the announcement that the Werewolf Game will begin again, now with the two of them as the werewolves. The protagonist grimly says that she will do whatever it takes to survive.
One episode where Kino helps a stranded group of people survive a harsh winter, we found out they were slave traders who had eaten their previous haul and look to enslave Kino to make up for it.
Another episode has Kino visiting neighboring countries who used to constantly be at war. When Kino asks how they achieved peace, she finds the opposing countries have made their battles into a game in which both countries see who can slaughter the most inhabitants of an adjacent defenseless village. And just to twist the knife further, the "innocent victims" in that village have taken to senselessly murdering travelers, simply as a means of venting their frustration.
In another episode, Kino finds a country so likable that Kino nearly breaks the three day rule of staying in one place, yet the townsfolk mysteriously refuse to let her stay longer. When Kino leaves, the next day she wakes up to find the country destroyed by a nearby erupted volcano.
The post-apoc manga Meteor ends like this. Throughout the entire series, characters try to find food, shelter, locate their families...and most die before they can achieve this. Then the few survivors left reach a village, but everyone there starts to go insane. Then some government officials arrive and say there was no end of the world, but the town and the village were used as experiment-grounds for new weapons and drugs, and that the seemingly-insane people will be given proper treatment in their hospital. But the protagonist wants to take the sweet little boy, who went insane and ran off earlier, with them, and she and Alpha Bitch go to find him. But in trying to catch him, the protagonist and the little boy fall off a cliff, becoming gravely-injured. The protagonist calls up at a-bitch to help them...only for the girl to run back to the rescue-helicopters and lie that both the protagonist and the boy went crazy and died. The manga ends with the protagonist screaming and crying for help as the last of the rescuers leave before sadly accepting her and the boy's fates as they slowly bleed to death.
The climax in episode 45 of Mobile Suit Gundam: Iron-Blooded Orphans has Shino pulling an all or nothing move to destroy Rustal Elion's flagship with a railgun. Just as it looks like he's about to blast away Rustal and put an end to the conflict, he gets hit from behind and misses his only shot. Cue Rustal winning the battle and spending the rest of the series chasing down Tekkadan, only relenting when he has crushed them so thoroughly that they no longer pose a threat to his now ultimate power, and one of the most depressing (and controversial) endings in Gundam history.
Most chapters of Nightmare Inspector generally seem like they'll end happily, with the client apparently getting over their nightmare's troubles, until some reveal or twist comes out of nowhere and sends things into a Downer Ending, or a bittersweet one at best.
One Piece: Luffy ran a "rescue Ace" mission for several dozen chapters to save his brother from being executed, sacrificing years of his life and culminating in his arrival at Marineford during the Paramount War, where he was out of his league and sustained even more injuries. And after everything Luffy went through to save him—after he'd successfully freed him—Ace was goaded into a fight and died anyway, becoming the first named character in the series to die onscreen outside of a flashback.
Paranoia Agent. Just one example: was it really necessary to kill Kozuka just to prove he wasn't Shonen Bat/Lil' Slugger? Maybe, maybe not. But he would've committed suicide anyway. Have a nice day!
Downplayed in Parasyte. Everything seems to be wrapping up nicely, Shinichi's got a happy life now. However, in the final chapter, the serial killer the police had enlisted to help spot parasites comes back for Shinichi, and after almost slitting Murano's throat, he tosses her off the top of the roof he's cornered them on. Cue panels of Shinichi reaching for her and failing, until it's revealed it's all in Shinichi's head and he was able to grab her arm with the help of a still-dormant Migi. The manga ends on a positive, if very abrupt, note.
Platinum End: After a new God is finally chosen, the last two chapters are spent watching him observe Humanity. When he views Humanity's numerous ills, he questions his and Heaven's roles in their development, and ultimately decides to leave the fate of the world in Humanity's hands to see if they would do better without him...by which he accomplishes through celestial suicide, nuking himself, Heaven, and the angels...whose existence turned out to keep Humanity running. The manga ends with every last human on Earth dying from youngest to oldest.
Viewers of Saikano often comment that if you want a happy ending to the series you should stop after Shuji and Chise skip town and go on the run from the military, because the final three episodes go quickly, horribly and tragically downhill after that. In the manga, this point is in the middle of the second of its seven volumes.
The three-chapter manga School Mermaid ends with the protagonist watching in horror as her best friend eats their mermaid-ified classmate, and is then coolly informed that she, the protagonist, will be turned into a mindless mermaid herself, and is dragged screaming by the other mermaids through the floor—her last sight being her best friend smiling cruelly at her with blood dripping out the corner of her mouth. The final few pages, focusing on the best friend, reveal that in a few days time, she'll kill and eat the protagonist too.
The Shadow Star manga ends with Shiina's mother being killed, her best friend killing herself, her boyfriend dying of cancer, her monster partner dying, and then Shiina fully realizes her God powers and decides to destroy the entire planet and reboot the world with her and another girl's children. And this is AFTER they've defeated the Big Bad.
At the climax of Ken's war on the White Dragon Clan in Sun-Ken Rock, Yumin suddenly realizes, from out of nowhere outside of a seemingly bogus accusation by an antagonist, that what she really wanted all along was not to destroy her father's yakuza organization, but to take it over instead. Embracing her true nature, she blasts her beloved Ken out of the building. It is downplayed, however, in that Ken manages to survive the long-ass fall and eventually rebuilds his mafia empire by taking over America.
One of the earlier examples being The Kind Mama's House, in which the child protagonist discovers her online friend, "Mama", is apparently stalking her and plans to kill her mother so she can be the protagonist's "real" mother. She manages to rescue her mother and demands Mama go away, and she does...only to show up in the protagonist's house days later, having decided simply to kidnap the girl, just like she did numerous others before her.
One of the special chapters Guard of the Mountain has a small group of camping-trip students getting lost with their teacher. They make it to a little camping ground and the owners merely ask them all to be 'on their best behavior' while staying. People begin to disappear and the owners turn out to kill people, who do not treat nature well, by littering or other means. After running away and falling, protagonist Hitomi finds herself taken in by a young couple and she realizes that she's managed to get away, only for the couple to bring her to the previous, dangerous camping grounds. And an extra page shows that the murdering owners opened up a beach house, implied to continue their little 'test' on people.
The Girls and Boys story has Yuuki think that boys have it easier, as they don't bully each other or gossip a lot and wishes that she'd be a boy and promptly finds herself in a parallel world, where she is 'Yuuki-kun'. But she soon realizes that boys are just as likely to bully and gossip about each other, sometimes worse than girls do. To top it off, Yuuki realizes that she still feels like a girl, even in a boy's body, and falls for 'his' best friend, Inoue. During a confession, turns out that this world's male Yuuki had a crush on Kaho, but then the entire class begins to tease Yuuki over being gay for Inoue and Yuuki ends up beating his tormentors to death with a chair. Wishing for things to go back to normal, Yuuki finds herself back as a girl and is intent on just being happy with the person she is... only to learn that the same thing happened here (with the original male Yuuki having confessed to Kaho and being teased as lesbos) and Yuuki has killed several of her classmates with a pair of scissors.
