There’s a key transformative moment in the 5th episode of White Album 2 when the 3 characters that are the focus of the love triangle at the center of the story begin to care about each other as a group. Setsuna and Haruki leave their own classes in order to console Touma after she ran out of class with the score she was working on. Up until that point, these were largely characters that were acting as individuals acting on their own teenage hormones or path of least resistance. So what changed?
In the previous episode, there was the important scene where Setsuna proposes they play a 2nd song for the festival that has a difficult guitar solo in it. The end result is that Haruki has to spend another week with Touma learning how to play this song, but it’s really the sum of 3 different decisions. For Setsuna, she really loves the song and wants to perform it for that reason. For Touma, despite it being a song far too complicated for Haruki’s skill level, it provides an excuse to spend more time with him so she pushes him that way. Haruki, on the other hand, accepts the decision of the other two passively despite being against it. That arrangement worked for a while until Setsuna found out at the end of the last episode.
So what would have changed? It really came down to making Haruki care by putting him in a situation where he can’t take the easy way out. The two conversations with Setsuna were important for the development of his character.
The first on the walkway came from the misunderstanding at Touma’s house. She ran away believing that Haruki was with Touma and that she no longer had a reason to get in their way. Then, she realized that the reason she liked him was his biggest character flaw. He treated her like everyone else, which she genuinely liked, but he treated everyone the same. In order to make the performance work and for the friendship she wants with Touman and Haruki, he had to change at least as far as making him see the other two as special.
That’s where the phone call later in the episode comes into play. Without going into too much detail about the cultural importance of it, Setsuna’s insistence that Haruki call her by her given name is critical. With that in place, he could no longer treat everyone the same. She became special to him.
As far as Haruki’s concern for Touma, that comes up later in the episode. During the test, he has to think about her role in appealing to the audience at the festival. It doesn’t mean much at this time, but the seed was planted enough to know where she would go after she stormed out of the classroom.
Finally, there’s the question of where Touma’s feelings lie. She has feelings for Haruki because like Setsuna she was treated just like everyone else. While she refuses to call Setsuna by her given name in this episode and outwardly views her as an annoyance, she cares for her just as much. She takes on the festival concert because she insisted. She hid Haruki’s overnight stays because she was worried about Setsuna misunderstanding the situation. She works on the performance to the point of exhaustion and in the critical moment for the group, she doesn’t want to be seen as holding Haruki and Setsuna back. The fact they begin practicing in the music room meant she accepted them as much as they accepted her.