Hinata's love for Miyako is so massive, she accidentally places her on a high pedestal by exaggerating how great she was. Goes to show how much she loves her big sister unconditionally.
Every time Hinata says "Mya-nee!". Good lord.
Noa's friendship with Hinata. Hinata proclaims that she loved her as much as her big sister, and provides her with emotional support. For Noa's side, she enjoys playing with her and is generally depressed and gloomy when Hinata isn't present.
While others may not appreciate her nor depend on her, Kanon holds an unceasing respect for Koyori. Her immense respect towards her friend is even more heartwarming when one considers how much more competent Kanon is than Koyori.
Miyako and Hana's friendship growing over the series, as Miyako learns to be less obsessive over Hana and Hana starts seeing Miyako as a big sister figure.
Anime
Episode 1:
While she is still creeped out by her antics, Hana offers Miyako her friendship so she wouldn't be sad about not having any friends.
After getting Miyako in trouble with her mother over making sweets before dinner, Hana apologizes to Miyako for it.
Episode 2:
When Noa gets upset because the girls weren't taking a cosplay contest she came up with seriously, Hinata compliments that she thought Noa was the cutest. From that point, Noa began to develop feelings for Hinata.
Episode 3:
When Hinata gets mad at Miyako because she felt left out from being the only one without a costume, Miyako offers to let her join her in the bath. As the two are bathing together, a flashback of Miyako when Hinata was born shows how close the two have been. Miyako comforts Hinata and let's her know that she still loves her. And as they go to bed Miyako promises to try and let Hinata sleep in her bed with her at least once every three days.
Episode 4:
Koyori trying to win a prize for Kanon at the festival. While she fails spectacularly, Kanon wins two bracelets, and gives one to Koyori as gratitude.
If one takes a look at the ribbons on Kanon and Koyori's kimonos, Kanon's is messy and untidy while Koyori's is perfect, which seems uncharacteristic for both of them. Therefore it becomes clear that Kanon tied Koyori's ribbon and Koyori Kanon's ribbon; despite Koyori doing a messy job Kanon wears it happily.
Episode 5:
After failing to make herself the image of perfection to Koyori and Kanon, Kanon instead hugs Miyako, complimenting her about how hard it was for her to pretend to be something she wasn't, going as far as to say that she was even better in spite of the rumors. For her part, Koyori offers to give Miyako a hug.
When Kanon has her hands tied up by Koyori, she expresses nothing but genuine faith in her abilities to untie her. This segues to a flashback where as young girls, Koyori climbs a tree in order to retrieve Kanon's balloon. Kanon is overwhelmed by this, she cries because she thought that Koyori was going to die.
Episode 6:
Hinata forging a friendship with Koko over their shared interest for Miyako.
Miyako calling Koko her friend while still being unsettled by her stalking.
Before meeting Hana and Noa's mothers, Miyako dreads it because she thought that they were going to report her to the authorities because of her taking pictures of their girls in cosplay. Instead, Hana's mother (Haruka) praises her for opening her daughter up, noting that she would be more distant. Koko also backs Miyako when she was unable to respond quickly to the mothers.
Episode 7:
When Hinata gets a fever and is forced to stay home from school, she feels sad when Miyako has to go to college. But when Miyako notices how sad Hinata is, she decides to stay home in their mom's place to take care of Hinata since the class that day wasn't required. And when Hinata is feeling better as their mom comes home, Chizuru tells Miyako how proud she is for taking good care of Hinata while she had a fever.
Hana giving Miyako a birthday present after jokingly trying to make her give the "I Will Do Anything" ticket. Just another instance of her slowly becoming more use to Miyako.
Noa offers to take Miyako's place for the remaining days after Hinata began to unravel due to Miyako forcing her to loosen her attachment for five days.
The second her punishment is over, Hinata jumps off of the disguised Noa and latches onto the real Miyako again. Noa is dejected that she was just a stand-in for Miyako, Hinata runs back and thanks Noa for her effort.
Noa: It's okay. It's not like I did anything important. I just dressed up as Mya-san to make you feel better. Anyone could do that.
Hinata: Don't say that. It's not like just anyone would have been okay. The only reason you could be Mya-nee is because I like you just as much.
Keep in mind exactly how much Hinata loves her sister. For her to compare Noa to Miyako is some incredibly high praise.
Episode 8:
Miyako and Hinata spending a day outside of their house. Though Miyako is spooked by some eager store employees, she seems to enjoy spending time with her younger sister.
When the girls meet Yu, she's lost and they bond with her. Then it's revealed she's Koko's little sister and the two share a moment being happily reunited. When Yu thanks them for helping her, the girls begin to gush over how cute she is.
At the end of the episode, Yu and Koko are taking a bath together showing how close the two are.
Episode 9:
The duration of Hinata and Noa's date is this, but the pivotal moment of this is Hinata buying the hair band Noa spotted earlier.
Another highlight is when Noa accidentally messes up the sandwiches that she had worked so hard to make for their date, only for Hinata to eat them anyway and call them delicious. Noa is so flustered that she has to hide her face.
Her disappointment in her aside, Chizuru nevertheless loves Miyako.
Miyako taking care of the girls while her mother gets stuck at work.
When Hana is still frightened from the horror movie they watch, she asks Miyako to walk to the bathroom with her. And then she asks Miyako to stay by her side until she falls asleep. Miyako then comments on how nostalgic she feels because of how often Hinata would cry when she was younger.
Episode 10:
While she does a bad job due to her clumsiness with her fingers, Hana beams with pride after fixing Noa's hair.
Hana requests Miyako to work on her hair. Definitely a major improvement from her previous discomfort towards Miyako.
Miyako and Hana bond while traveling to the bake shop to buy some fresh creampuffs.
To a certain degree, Miyako's assurance to Hana that she'd continue to make sweets for her even after she left the house.
Episode 11:
After helping the girls with making costumes for the school play, Miyako decides that she would attend the culture festival, solely because Hana and the others were in it.
Hana is initially nervous when the play is about to begin, but after seeing Miyako in the audience, she starts to feel better.
When Miyako starts feeling nauseous from being in a crowd, Chizuru tries to help her calm down.
Episode 12:
The play itself is about how an angel fell in love with a human girl and risks going through snowy mountains just so she could become human and be with her. Even though her love interest died, rather than disappearing, she bonds with her granddaughter and they work together to upkeep the baker shop. When she died, not only did she become an angel again, but she also reunited with her lost love.
The teacher compliments Miyako for her costume designs, and it's ultimately shown once and for all that the trio's fellow classmates adore her...even in spite of them jumping to conclusions about her due to the rumors
Miyako actually making the effort to go to the play and even meet with Hana's classmates for a while despite her crippling social anxiety, just because she wanted to see Hana and the others perform that much.
When Miyako gets overwhelmed and runs off, Hana finds her and tells her that she "doesn't dislike" how Miyako gives it her all when something's important to her before taking her by the hand and leading her back to the classroom. It shows how both Miyako and the relationship between her and Hana have grown over the course of the series.
She hung in there.
At the end when Miyako is taking a bath, Hinata, Noa and even Hana join her on their own will. While it's shown that Miyako and Hinata bathe together sometimes, the fact that Hana is willing to share a bath with Miyako shows that she feels safe around her.
OVAs
Miyako slowly beginning to enjoy spending time camping with her friends and family. When she and the girls hear something rustling in the bushes, Miyako took it upon herself to protect them despite being equally terrified.
Several of the girls' Halloween costumes are adorable, even Hana's Zombie Higero costume. That confident smile Hana has during a smash cut really sells it.
The final segment of episode 13 is a flashback of Miyako preparing for her baby sister's arrival with stuffed animals. After Hinata's birth, the first thing that she saw was Miyako. From there, the two formed a deep bond that continues in the anime series.
