Kaosayo

"Hmm... Seta-san was the most memorable. By teaching the guitar with her, I was able to gain insight into the professionalism with which she approaches the stage. Simply seeing the extraordinary lengths she goes to for the sake of the audience was an educational experience."

- Sayo in "Challenge the Teacher?!"

Kaosayo is the femslash ship between Kaoru Seta and Sayo Hikawa from the BanG Dream! fandom.

Canon
Kaoru and Sayo are guitarists of their respective bands, Hello, Happy World! and Roselia. They are both third-year high school students, although they attend different schools - Sayo attends Hanasakigawa Girls High School with the rest of Kaoru's bandmates, and Kaoru attends Haneoka Girls High School with Sayo's younger twin sister, Hina. Sayo is serious, very dedicated and can be quite blunt, whereas Kaoru is more bombastic, very theatrical and quite silly, tending to misquote Shakespeare and describing things as "fleeting" or explaining things she can't properly understand or explain with a "It is but that." Despite Sayo's serious nature, it is most likely due to her sister's influence that she has come to somewhat understand abstract terms, and become more curious about them as well, seriously wanting to learn about them.

Prior to the event which also featured them as the gacha 4* pair, Kaoru and Sayo barely had any interactions, most of them happening through a proxy - Hina explaining something Kaoru had done or said and Sayo reacting to it. At one point Sayo also mentions acknowledging Kaoru's guitar playing skills.

Melody of the Dignified Wind
The event centers around Sayo, Tae and later Kaoru as well teaching Touko about guitar playing as the latter hone her skills before an exam and in order to prove Morfonica's violinist and composer Rui that she can play the part - which happens to be the song's highlight - perfectly. In Chapter 3, after Sayo does her best to understand how Touko had suddenly gotten better, she and Tae end up witnessing Kaoru and Misaki with Touko practicing, and Touko jumping around in high spirits, attempting to mimick Kaoru's playstyle. In Chapter 4, when Touko explains how it's easier to play when she does the same moves as Kaoru. Sayo finally deduces what exactly helped Touko fix her bad habits. Kaoru expresses it was thanks to the power of fleetingness, and when Misaki tells Kaoru it doesn't explain anything, Sayo agrees with Kaoru. Misaki is caught off guard, then asks the ever-serious Sayo if she is joking, and Sayo starts explaining how Kaoru's habits "overwrote" Touko due to the latter's mimicking. After Kaoru quotes Shakespeare, Misaki tells Sayo she can just ignore her, but Sayo takes her seriously, thinking what Kaoru meant with the quote was "need to question our preconceptions if we hope to achieve better results". Misaki is even more surprised when Sayo asks if Kaoru could teach Sayo as well, saying she wants to see guitar playing from a different perspective, different way of learning and in order to find any possible new discoveries. They play together and then Kaoru explains what she tries to convey while performing as Sayo absorbs the information. When Tae suggests Kaoru and Misaki join their practice sessions with Touko, Sayo agrees with her, saying it would be the most efficient choice in their current situation.

In the Ending Chapter, Sayo is fidgeting around and very worried just before Touko's concert, wondering if Touko will be alright. During her performance, the four watch Touko playing in tense spirits, cheering each time she manages to perfectly play each of her parts, and Kaoru comments how "it appears words are unnecessary [to describe it], the cheers are a reflection of her efforts." While in the lobby after the concert, Misaki points out Sayo is crying. Sayo denies it, explaining how it had been surprisingly and more nerve-wracking than being onstage herself, and how she had not realized she had been so engrossed in the concert. Kaoru also says she hadn't noticed how engrossed she had been as well, and tells Sayo they all should go greet Touko and express how they felt about the show. Sayo agrees, saying that it was a good performance but how they also need to tell her that Touko still has room for improvement.

In Misaki's Card Story Episode, titled "Piled Up Feelings", Misaki calls out to Sayo while she's in the CiRCLE Café during one of their breaks from teaching Touko. Sayo asks Misaki for a favor and help, and then proceeds to show her a notebook where she had written down every use of the word "fleeting" she had heard Kaoru say no matter the context. She explains that she is trying to understand the concept of fleeting, and how it exactly helped Touko lose her bad habits. Misaki helps her out, explaining one of Kaoru's phrases to her, before revealing it's highly likely Kaoru doesn't fully understand what "fleeting" means neither. Sayo is shocked about the reveal, and mentions that going off of feeling is a difficult concept for her. The episode ends with Sayo asking Misaki if she could ask her about Kaoru starting from now, because she seriously wishes to learn.

Quotes
"Fleeting is an abstract concept. Kirigaya-san may misinterpret the term, so I have attempted to categorize each usage. Seta-san has helped Kirigaya-san's playing improve in ways I had never conceived of. It is as she said... We must question our preconceived notions if we are to improve. If I can maintain an open mind as she does, I believe I will be able to improve my playing further. However... Fleeting performance, fleeting sound, fleeting heart... I can understand these uses, but there are many that are beyond me..."

- Sayo in "Piled Up Feelings"

Fanon
Kaosayo is a big rarepair. Aside from the girls' most popular ships, Kaosayo is sometimes rivaled by other Kaoru and Sayo ships such as Kaotomo and Sayotomo. Prior to the Melody of the Dignified Wind event, some fans had already shipped them due to their opposite personalities, the fact they are both guitarists (mostly as an extension of the poly ship between the five original guitarists) and imagining the ways the two would interact, with some of the examples being how Kaoru could charm or fail while trying to charm the more reserved Sayo as well.

Fandom
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