Tear Jerker / Souls Art Online

• Chapter 28 has Silica sacrificed to the Moonlight Butterfly, being the first real causality in the game since she doesn't respawn. Kingseeker even shows her dying in the hospital room to prove a point that she's really gone.
• Chapter 35:
  • Ashaeron performs a Sacrifice to subdue several enemies before telling Kirito not to waste it.
  Ashaeron: "Herald-I'm sorry. We held them back...for as long as we could...do not let our sacrifice-wait-ah...I see. Herald...the game for me ends now."
  • Kirito slays the boss. The boss was a child who died as a result.
  "Say hello to the players of Souls Art Online, Nito," Kayaba said with a small smile. "If they are seeing this, then it means they defeated you."
  
  "Oh," Nito, a small boy without hair and sunken eyes, looked back with a tired expression, but there was happiness in his eyes all the same. "I should feel sad...but I hope they had fun," he added honestly. "I hope my mom and dad watch this."
  • Chapter 36 shows the fallout with Kirito and a number of the raiders. It's... disheartening.
  • Chapter 38 ups the pain-train for Kirito, who learns that the Gravelord Servants didn't kill Solaire despite believing that it would hollow them, and he's attacked by Way of White members who accuse him of cheating. It quickly leads him to his Rage Breaking Point.
  Kirito: "I grow tired of this. I want to finish this game. I want to wake up. I want to go home. I don't care about humanity, about being tested, about...everything else. I want to go home. And you should want to go home too. So why? Why did you attack? Why did you have to do that? Why did you have to let your jealousy and greed dictate your every, pathetic, move?! Look around you!"
• Chapter 39 shows no sign of stopping the heart break with Asuna recounting what happens on the other side of the portrait being so horrifying she considers suicide until Kirito stops her.
  Asuna: ...And if you wanted us to feel the same despair you felt clearing ahead of us-well, you managed it! I-I just had to bring this back, for the others-now...now if there's nothing else, I just...I just want to leave."
  Kirito: Wait! you aren't planning-
  Asuna: Even if I were, what right do you have to stop me?!"
  • The only reason she doesn't is because Kirito had to logically appeal to her by telling her that Kingseeker would be stronger because of it.
• Chapter 40 has Priscella stating she was imprisoned for being BORN. She actually starts breaking down in tears while explaining what is happening in the world.
  • Strea and Yui have been imprisoned for their own sake due to the promise that anyone that slays them will be freed.
• Chapter 42: Oscar is dead. Yuuki, as unpleasant as she was, had been turned into a Black Knight and killed, and Silica's shade seemed to have regained sentience just long enough to ask Kirito what was going on.
• Chapter 46: Strea and Yui appear to have been killed off-screen and Kingseeker revealed that several of the players are Dead All Along.
• At this point, the death of any boss because Kingseeker, being a dick, shows that the people used to make them are decent or sickly or pin their hopes on Kayaba, only for him to use them like this.