Bittersweet Ending/Web Original

At the end of Kate Modern: The Last Work, the main characters celebrate with a party. Except Julia, who winds up pregnant with a trait positive baby that isn't even genetically hers, with her husband apparently dead, her source of money presumably gone as well, and her friends alienated. Poor Julia.
In the last episode of Red vs. Blue, they defeat Omega and Wyoming and tie up all the loose ends of the earlier time loop, but apparently lose Sheila, Tex, Andy, and Junior in the process.
- The Recollection trilogy is even worse:
  - Reconstruction ends with the Big Bad seeming to have been defeated, and the Reds and Blues have new bases, but Alpha-Church is permanently destroyed, along with Delta, and Washington's fate is left ambiguous.
  - Recreation ends with Church having been revived in spirit as Epsilon, the return of Tucker, and one of the season's two big bads finally killed, but the Reds and Blues apparently have to fend off a force of aliens. Meanwhile, elsewhere, Agent Washington pulls a Face Heel Turn and kills two major characters.
  - Revelation has Washington pull a Heel Face Turn, and the Reds and Blues finally kill the trilogy's Big Bad, and all go off to continue their Red-Blue battles. Unfortunately, Epsilon is trapped in a powerless memory storage unit, unable to escape, trying to find Tex, though he seems fairly content with his circumstances.
Dr. Horrible's Sing-Along Blog ends with Dr. Horrible achieving his greatest ambition - getting accepted into the Evil League of Evil. However, while pulling the heist that put him on the A-list of villains, he indirectly caused the death of the girl of his dreams. The finale song shows the Dr. Horrible, all the good in him seemingly dead, gloating about his victory and warning the world that "now the nightmare's real". However, the last shot is that of Billy (Horrible's human alter ego), clearly lost and heartbroken, staring blankly at the webcamera.
Half Life: Full Life Consequences ends with the Combines being defeated, but both Gordon and John Freeman dying in the struggle, with the latter holding the Combines back to buy time for the 'humens' to escape. But now the ~~humans~~ humens are at peace, with Henry Freeman as their president, and at the end of the Djy1991 version, you can see Gordon, John, and several others rising up to heaven.
Nuzlocke Comics invariably end like these, seeing as the protagonist would have lost many friends along the way. No matter how happy the author might try to make the the ending be, it will always be permeated by the feeling of loss and lonliness, both by the reader and the characters.
The Half Life fan-film Beyond Black Mesa, ends with the transmission sucessfully going out, but Adrian and the remaining rebels blowing themselves up when they're cornered by the Combine.
Suburban Knights ends with Team TGWTG saving the world, but at the cost of Ma-Ti's life. The team reflects on the loss, with Spoony breaking down during his Final Fantasy XIII review and The Nostalgia Critic lying in bed.
In Greek Ninja, the battle determining the fate of the world was won by mankind, thanks to Sasha, however Iphigenie was amongst the casualties.
I Love Bees: The assembled team seem to have saved the world and have been united with their family or otherwise reached a happy end despite their losses. And then the Covenant turn up.
Dragon Age Redemption ends with the saarebas re-captured and his plans foiled, but the templar Cairn and Josmael's betrothed are both dead. Tallis kills the saarebas to avenge Cairn's death, thus failing her mission. Nyree even states that it doesn't feel like much of a victory.
Season 5 of Arby 'n' the Chief has the duo stop the wedding of Gaming Tycoon, Trent Donnovich, (after the latter was caught cheating on his fiancee and Arbiter's Girlfriend), but at the cost of Arbiter and Chief's only access to the outside world, Xbox-Live.
- While not exactly being the end of the season itself, Kylie of Season 6 suffers one when she is banned by Arbiter and Chief and is stuck living with her father, who is revealed to be a cruel alcoholic, and is without any means of escape.

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