The ending of Will's character quest. Wherein the player and Harriet learn of the well-detailed room that Will kept just for Harriet. Even more heartwarning, Will and Harriet sit down on a field, and Harriet asks Will what the flower he and Amelia discovered and named. Harriet was brought to tears, after having treated Will like crap throughout the entire "main quest" and first chapter of the Character Quest.
Amelia: So, professor, did you think of a name for the flower? On three, okay? Ready...one...two...three...
Will and Amelia: Harriet.
Pretty much any scene between Jay and the Oresoren. It's simply ASTOUNDING the lengths they'll go to for his sake, such as appearing on a dangerous battlefield just to cheer him on, or taking on world-class assassins leagues above them in power to try and rescue him.