Just seeing so many of Asami and Korra's friends be so accepting of them being a couple and happily congratulate the two is enough to bring up some tears.
Korra telling her parents that she and Asami were together. While they are happy for them, they warn Korra that not everyone would be as accepting as they were and to keep their private lives to themselves. You can tell even when Korra argues why she has to hide who she loves, her parents are just trying to protect her.
Kya telling the two about each nation's history regarding LGBTQ+ people. While the airbenders were totally accepting, and the water tribes were fine with homosexuality (albeit preferring to keep their private lives private), the other two nations weren't as understanding. Before Sozin came into power, the Fire Nation was tolerant to homosexuality, but when he reigned, a panel of two women being led away in cuffs is shown. Even Avatar Kyoshi, who was said to be loved by both men and women, couldn't break the Earth Kingdom's intolerance.
Korra starts to worry about her relationship, thinking that if Kyoshi - one of the strongest Avatars - couldn't bring any kind of positive change for LGBTQ+ people, what chance does she have?
Korra trying to explain why she wouldn't close the spirit portals and asking why the spirits and humans couldn't just coexist. The dragon-eel spirit argues that he's only lashing out to protect his home from humans who wish to abuse their land.
While trying to stop the dragon-eel spirit from harming Tokuga, Korra sees Asami take a hit form an earthbender and immediately turns around in order to protect her girlfriend and see if she's okay.
Tokuga on the other hand gets momentarily possessed by the spirit. Even if this guy does deserve this punishment, you know his transformation will be far from pleasant.
After The Big Damn Kiss of Asami and Korra and they tell their friends that they were together, it's heartwarming to see everyone supporting them and Bolin suggests they go on a double-date.
The Fridge Sadness of Asami revealing during the vacation that the reason she didn't tell Korra she loved her during the Time Skip was that she was afraid Korra would be turned off and never come back. Considering how much the universe unfairly loves to just shit on this woman before and after this revelation, it's heartwarming that Korra felt the same way, but heartbreaking that she was dealing with this the whole time they were separated with apparently nobody else knowing this and it being unclear as of Part 2 as to what exactly is Republic City's stance on queerness, let alone one of it's biggest VIPs that's been repairing it being in love with The Avatar.
Korra takes the airbenders to the spirit world and is horrified to see the once lush and beautiful landscape turned into a dull withered husk. Tenzin tries to console her and says he knows how much this place meant to her and Asami. Korra then deduces that the spirits purposefully destroyed their own land in order to send a message: Humans are not welcome here.
Especially sad when you remember how much the relationships between the spirits and humans improved over the events of the animated series.
While the spirit world isn't the safest place in the Avatar world, seeing the plants attack the airbenders, causing everyone to flee back to the human world is frightening.
Raiko turning the people onto Korra, calling her out for going on vacation so soon after their city was destroyed by her and Kuvira. Asami and Tenzin try to stand up for her, but Korra quietly tells them to let it go as she hangs her head.
Asami is confronted by the Creeping Crystals who offer to be her bodyguard if she pays them. When they leave, she lets out a relieved sigh, but looks incredibly stressed as she hunches over the table.
Korra meets Asami the next day and when she find out about the Crystals, she offers to go beat them up for Asami so they wouldn't bother her again. Asami tells Korra that she can't have the Avatar solve all of her problems and adds that she doesn't need Korra's help, causing her to turn away in frustration.
However their argument is simmered down when Korra admits that she's just worried about Asami because she cares for her so much and doesn't want anything bad to happen to her girlfriend.
As Korra waits for Asami at the restaurant for their date, she stares at the clock and after a half an hour leaves to find the nearest phone box. She calls Mako and Bolin to tell them she thinks Asami's missing, adding that she wouldn't have stood her up and suspects the Creeping Cyrstals.
Just seeing Korra run to Asami's office to find not only a beaten down trailer, but her bodyguards almost all knocked out.
Korra angrily threatening the Creeping Crystals and saying they would pay if they had hurt Asami.
Tokuga smugly tells the group that they were missing one member and that's enough of a hint for Korra to angrily lash out at him.
When Tokuga points to the sky where a blimp hangs Korra can only stare on in horror as he tells them Asami was up there and if Korra were to fight back, they would hurt her.
Korra: This is my fault.
Asami's expression is no better as she watches the flames grow. She's cuffed, held at fire-blade point and all she can do now is look down at worry for her girlfriend.
The book ends with Tokuga ordering his men to march on Republic City as the flames slowly grow.
How stressed and tired Korra looks when the others gather around the turf of the Creeping Crystals that Tokuga took over. It's clear that she's worried about Asami's safety and Lin even walks over to her with a reassuring hand on her shoulder.