Tear Jerker / Long Road to Friendship

• When Fluttershy's supervisor Ms. Tenderheart at the animal shelter confronts Sunset about her bullying, we are treated to learning about what the consequences were of the latter's actions. Not only did Fluttershy come to the shelter almost every day in tears, there were one or two instances she contemplated suicide just to escape it all. Even Sunset couldn't believe how far she pushed her.
  • What makes this worse is because Sunset broke up all their friendships prior to Equestria Girls, Fluttershy had literally no one to turn to for what was likely nearly 3 years of loneliness.
• At the Halloween party, Sunset endures yet another nightmare that jolts her up in the middle of the night. While getting a drink to calm her nerves, Twilight wakes up and asks her what's wrong. Then Sunset's pride suddenly shatters like fragile glass and she breaks down into a sobbing mess, crying and pouring her heart out to Twilight over her past transgressions and heinous activities. It's so jarring to see Sunset become so vulnerable that the only comfort she could find at this moment was Twilight.
• Chapter 24. Sunset finally clues in that Twilight might have feelings for her. She initially brushes the idea off as silly since of course Twilight would never be attracted to her, they're Just Friends. Then she thinks that if Twilight did have feelings for her, "[I’d] stomp her heart flat", because Sunset isn't into girls anyway. It's not often an author does a Ship Sinking of the ship the story is based on.
• Chapter 26, "The Rise and Fall of Sunset Shimmer." It features a lot of Call Backs to canon continuity, like Sunset being an arrogant bully who felt she deserved to be a princess, but it's all told from Sunset's perspective instead of the third-person narration the story had been using. The Character Development Sunset had been going through shows here, as she lays out the myriad of ways she was terrible to her parents, her mentor, and anyone who showed her a shred of kindness. It makes it all the more sad when Sunset walks up to the statue that links Equestria and the human world at the end of the chapter.
  Sunset: Mom, Dad, Celestia... I'm sorry.
• Chapter 30 has Lyra smoothly, casually tell Sunset that, if the Winter Ball doesn't make money, Sunset will be banned from all future school events. It's heartbreaking to see how much of a scapegoat that Sunset's become.
• Chapter 31 ends on a pretty big tear jerker. Earlier in the evening, Twilight has asked Sunset to "please lie" to avoid talking about Equestria, or being homeless. It works, but when Twilight privately asks Sunset how she feels about her, she still has to lie. Despite crying, Sunset says that she hates Twilight and despises their time together, inadvertently breaking Twilight's heart because of Sunset's curse.
  • It gets worse when Twilight tells Sunset to "please leave her alone," and again, Sunset has to do it. Sunset even notes that by trying to avoid breaking Twilight's heart, she'd done just that. All that time finally coming to grips with her feelings, and Sunset threw it away.
  • Made worse still in Chapter 32, when Sunset discovers that she physically can't tell anyone about the curse. Even if she'd wanted to explain the situation to Twilight, she wouldn't have been able to.
• In Chapter 34, the Humane Five and Sunset are at a pizza place, and the conversation turns to things said about them. It turns out the Humane Five all accidentally started rumors and mishaps with each other, and all of it comes to a massive head with a food fight. Despite Sunset's best attempts to pin this all on her, the Humane Five storm out, angry at each other. All Sunset can say is "Girls, please... don't leave me alone." The next chapter has Sunset all but cross the Despair Event Horizon, screaming "I hate you!" to her past self, even believing that she's worse off now than she was at the Fall Formal.