Tear Jerker / Anchor Foal

• The climatic point of chapter 17, where Fluttershy, after a disastrous date, manages to tell Caramel that she never wants to date him again before she flies away. Caramel is visibly heartbroken, especially because he has no idea why things went so wrong (long story short: jealous Discord), and thanks Fleur for at least helping him to get a date with Fluttershy, as he's been crushing on her for a while. Fleur just stays silent; her entire reason for setting Caramel up with Fluttershy as the latter's first date was because she knew that Fluttershy wouldn't like him, so she saw Caramel as the perfect patsy for Fluttershy to practice rejecting ponies on. It culminates in this exchange:

  Caramel: "Fleur?"
  She waited.
  "I'm... glad you're my friend."
  And she took her designated victim home.

• The story of the unnamed mill owner. You know from the state of the mill that something went wrong, but in Chapter 43 it's revealed that everything went wrong. The mill was in the process of failing due to financial difficulties and while the owner was trying to sort that out, his marriage completely collapsed, ending his hope for a foal. In the end, he abandons the mill, the friends he'd made, Ponyville, and Equestria.
• Fleur's backstory, as revealed in chapter 44. Long story short, she was orphaned at a young age when her sickly single mom passed away, got Happily Adopted by a family of griffon ranchers, her adoptive sister was left brain-dead fighting a monster to save Fleur's life, Fleur accidentally gave her sister a Mercy Kill whilst trying to help her get better, ran away from home because she couldn't handle the guilt, then was almost sexually assaulted by a pedophile unicorn neighbor who lured her in by promising her help. She only got away because she managed to gouge out his eye with her horn when he was shocked by the sudden manifestation of her cutie mark... which also awakened her ability to empathically sense his every single twisted desire for her. Then she had to hide in his house for several hours so she would have the cover she needed to resume running, which ended with her fleeing all the way to Equestria. And, for the icing on the cake, it's heavily implied the accident that resulted in her sister's death in all but name was the fault of that same pedophile neighbor, because he faked completing a vital job instead of actually doing it — which Fleur herself didn't figure out until years later, instead believing that she had somehow discharged the entire power supply herself! It really explains so much about why Fleur is the way she is.
  • Confirmed in the final chapter. The stallion's magic was so weak that he couldn't charge up the door, so he cast a low-power illusion to make it appear charged.
• In chapter 48, Harem Fantasy and Discord's final interactions.
  • Harem began worrying about what would happen to her when Discord was finished with her back when they visited Tartarus, and now the time has finally come that Discord no longer needs her. She promptly decides to Face Death with Dignity.
  • Discord, who had been about to just undo her creation, suddenly stops as the full impact of what he's about to do actually sinks in — that he's about to kill someone. He hesitates, trying to figure out what to do, and considers just leaving her as she is, maybe giving her to Twilight... then realizes that leaving her as a sapient book in Equestria would be even crueler, as Twilight and/or the Academy of Magic would basically condemn her to an eternity of testing to try and figure out "how" she exists without treating her with the respect they would give a fellow pony.
  • Harem Fantasy even asks Discord if they might meet again in the Shadowlands, because she hopes that she's alive enough to go to the afterlife.
  • Finally, Discord hits upon an idea, asks Harem if she will trust him this one last time, and then seemingly kills her. The weight of his actions hits him then, and when the Bearers (minus Fluttershy) catch up to him, he finds himself wrestling with grief for perhaps the first time in his existence, culminating in his reacting to their questioning him with a frustrated scream:
  Discord: "SHE'S GONE! ISN'T THAT ENOUGH? I HAD TO LET HER GO! WHY CAN'T YOU?"
  • Then the final reveal, which is a Tearjerker, Heartwarming, and even a little bit of Funny all rolled into one: Discord took Harem's soul from her book body and gave her a chance to truly live by incarnating her as a pony... Specifically, as a pony about to be born to a mare who only expecting one foal, not twins.
• In the Epilogue, Brass in hospice. Crosses over with Heartwarming, as he still remembers and thinks fondly of his friend from so long ago.