Also Fine reverting back to Ryoko and wishing Hibiki good luck before she literally crumbles to dust.
Episode 4 has Chris singing in front of the Academy at the festival, while reflecting on how she became friends with three other students as well as Tsubasa, Hibiki, and Miku. This is especially heartwarming knowing what Chris has endured all her life, especially when seeing her singing so happily and knowing that she has friends who rely on her. Even Kirika and Shirabe, their enemies, are moved by the performance!
Episode 12 has a flurry :
Maria finding a sense of purpose in using her song to activate Frontier to remote control the moon back into its proper orbit, and broadcasting it to the whole world, apologizing for her acts.
Tsubasa reminiscing Kanade and telling Chris her place is at their side against all odds.
Chris finally calling Tsubasa "senpai", and affirming their mutual trust as they pull an epic fast one on Ver, and Tsubasa bailing Chris out.
Fine saving Shirabe by taking Kirika's Swan Song (a strike capable of slashing down to the soul) and asking Shirabe to pass on her message to Hibiki.
Miku cheering on Hibiki as she dons Gungnir after stealing it from Maria.
The last segment of the first OVA: Chris prays for her parents at the Buddhist shrine she had Genjirou lug back to her apartment, telling them that even if she's not used to school life yet, she's beginning to enjoy it.
The reason of the very first set of actions: The Symphogears went through all the trouble to secure Prof. Nastassja's corpse just so she can get a proper burial. Hibiki's reasoning seals it: As far as she is concerned (and the rest of the good guys), the Professor's heart is in the right place, she wants to save the world genuinely, so she deserves proper burial!
A bit of Fridge Heartwarming; remember all of the trouble Tsubasa went through to get Chris to call her "senpai" back in the last season? Well, guess what Chris calls Tsubasa in her first spoken line of the season?
Tsubasa: These things are as wild a ride as Yukine herself!
Chris: Then show me how well you can handle me, senpai!
In episode three, as noted under Funny, Kirika took a shop sign for an impromptu cape...which she then later uses to give Chris some modesty when she rescues her, wrapping her in it.
A small moment comes in Episode 7 where Maria hands Tsubasa sunglasses to conceal her identity. These two used to be very fierce rivals in the previous season, so seeing them interact in a friendly manner really makes one smile.
Tsubasa: You're sounding like a mother, Maria.
Heck, all the interactions between the F.I.S. Children and the original 3 Symphogear users can count as this. Maria, Shirabe, and Kirika definitely put Hibiki's extended hand of friendship to heart and now each respective side puts the other above themselves. Hibiki, Tsubasa, and Chris want to protect the F.I.S. Children from the backlash of the public while Maria, Shirabe, and Kirika want to make up to S.O.N.G. for giving them a second chance at life in whatever way they can. And these were once people who fought each other to the death! Character Development at its finest.
Two moments in Episode 8:
First, when Shirabe swaps her apple juice for Kirika's black coffee, after the latter gets unlucky playing the vending machine lottery.
Secondly, when they realise that even though everyone was harsh to them on occasion, it was out of a desire to protect them.
Episode 9 is one very big Heartwarming moment for the Kazanaris. Even though Yatsuhiro continues to give Tsubasa the cold shoulder, Maria points out that Tsubasa's room, despite the ostensible mess, has been kept clean and dust-free for ten years, something that Yatsuhiro wouldn't have done if he really hated her. Furthermore, seems like being Cruel to Be Kind runs in the family - the reason why Tsubasa was asked to leave the family mansion was not to ostracize her, but to allow her to pursue her dreams, free of encumbrances.
Episode 10: The truth about Carol using Elfnein to spy of S.O.N.G. has been revealed and Elfnein appropriately asks that she be tied up and put elsewhere so that she won't be of any more harm. Response? Genjuuro pats Elfnein on the head and tells her that she doesn't have to go anywhere, with Sakuya and Aoi agreeing wholeheartedly. Cue Tears of Joy from Elfnein.
Episode 11: Hibiki's dad may be a complete ass throughout the series, but in this episode, he shows that in spite of his overall cowardice, he STILL cared for Hibiki, he used himself as a bait to Carol's blasts so Hibiki can escape and to fix their broken family she needs to survive, and proceeds to admit that yes, he's a Dirty Coward, but there's one thing he cannot hide from: being Hibiki's father and determined to protect her. And the real reason for that? Just to run to the dropped Gungnir relic and throw it back to Hibiki on instinct that she could be a Symphogear he watched back in G, and he's right. And from that point on, he decided that he'll stop running away and watch Hibiki's battles while cheering on her head on.
Episode 13: After the last battle, Hibiki comforts Elfnein in the hospital, who has fallen into critical condition, by telling her how fun summer vacation is. After they leave her room, she runs to the bathroom. Miku follows after her, which reveals her to have been crying. Knowing that she is essentially wanting to know why, Hibiki realizes that just punching things only solves the supernatural problems, not the ones that matter realistically. Miku, however, believes in her, holding her clenched fist, and believes that someday it will solve everything. We then get this exchange:
The Stinger also shows Hibiki finally reconciling with her family.
A debatable one from the third GX OVA, but when Carol tells Leiur to attack Elfnein so Elfnein could leave the Chateau faster, Leiur hesitates for a moment, saying that she feels sorry for the kid. This is despite the fact that Autoscorers aren't programmed to have a conscience or feel sympathy.