After booting Chloé out of her classroom, Ms. Mendeleiev checks on Marinette, tersely asking whether Chloé's "had too much fun these last few years" and reassuring her that she will NOT allow her to continue this harassment. The realization that she suddenly has a teacher in her corner after so many years without anyone intervening on her behalf spurs Marinette to Tears of Joy.
Marinette and Aurore's friendship, as the two of them offer each other unwavering support — and neither one takes the other for granted. There's no sense of obligation involved, with both properly appreciating the other's efforts.
Chapter 4 seems like a setup for a misunderstanding-induced blow-up, as Marinette doesn't arrive in time for Aurore to see her in the crowd for the Weather Girl contest, then finds herself face-to-face with Stormy Weather, who gives a With Me Or Against Me speech... then offers it up by patting her on the head and apologizing for the scare, leaving her completely unharmed.
Following Ladybug's clash with Stormy Weather, she immediately checks on her, then risks her secret identity by rushing back to her side as Marinette after detransforming, not caring whether it might seem suspicious for her to show up so quickly. Movie and cookie binging at the bakery follows.
When Mme. Bustier cheerfully reveals that Chloé is claiming that she can't focus as well without Marinette around and starts badgering her to transfer back — or consider mentoring her long-time bully — Ms. Mendeleiev steps in to defend Marinette again and force her meddling colleague to back off.
Kim, after a Jerkass Realization about his crush on Chloé (that led to his Akumatization), is the first legitimate member of Bustier's class to make a real effort to rekindle a friendship between himself and Marinette. He's the one who stands up for Marinette in Chapter 9, frequently making sure she's alright.
Despite the rocky relationship Ladybug and Alya have over the former's Secret Identity and the latter's desire to unmask her, Marinette and Alya actually bond over their mutual dislike of Chloé bullying people (especially Mylène during the Horrificator incident). Alya even advocates that Marinette leads them to try to escape.
After the movie making left a sour taste in Marinette's mouth, Aurore takes her out to an ice rink. She proceeds to stand up for her when the desperate owner tries to guilt-trip them into taking formal lessons there, and after Frozer's created, stands her ground against both the uncooperative Chat Noir and the akuma, hitting Frozer and Hawkmoth with a diatribe about how much they suck as villains.
Aurore and Mireille are handling the fallout of the Weather Girl competition with incredible tact. When Mireille ends up accidentally winning a competition she never intended to and is being pushed around by Alec, Aurore eventually talks to Mireille, and the two worked together offscreen to get Alec to hire Aurore (despite him CLEARLY not wanting to given Aurore's harder to control personality), and Aurore's being mentored by Nadja.
The party scene has several instances of Ship Tease... and there's no Akuma attack.
Jean sees Marc clinging to the wall, and the two bond over magic tricks.
Ondine and Kim both mutually decide, after sharing a dance, to bail on the party to go swim. They end up unintentionally taking the entire party with them.
Audrey of all people gets one while visiting the Dupain-Cheng's bakery. After commenting on how Chloé could learn a lot from Marinette, she's quick to reassure the clearly discomforted girl that that's nother responsibility, acknowledging her own shortcomings as a parent instead.
Aurore and Jean invest a lot into ensuring that Marinette has a happy birthday. Making things even sweeter, Master Fu chooses that as the day to distribute three Miraculi and give her more permanent allies.
Original Version
In the middle of facing her first akuma attack, Amber Bourgeois sees Marinette seeming stressed and offers her comfort despite her own distress.
Despite having plenty of reasons to dislike Alya for blithely ignoring Ladybug's wishes and pursuing her Secret Identity, Marinette still reaches out and tries to bridge the gap between them, offering her both comfort and gentle honesty after the Face to Face incident leads to backlash against the Ladyblog. And this pays off, as the two of them start forging an honest connection afterwards, with Alya set on a potential road to personal redemption.
Jean noticing Marc sitting alone at Chloé and Amber's half-birthday party and going over to cheer him up with a few magic tricks. No pressure to join the festivities, just sitting with him and making sure he enjoys himself.
Upon seeing that Chloé's cornered Marinette, all thoughts of sticking with Adrien and continuing to flirt with her crush go out the window as she immediately starts heading towards them. Adrien's attempt to stop her and claim that Marinette should keep putting up with it so Chloé doesn't get mad and create another akuma causes said crush to promptly evaporate entirely — you do NOT ask Aurore Beauréal to stand idly by for the sake of sparing some bully's feelings.
Amber also intervenes, making clear that she's not about to let her sister take out her frustrations on anyone else and asserting that Marinette is welcome there, as her guest.