Chie got stuck being on a committee for the joint school festival. Luckily, Yuuko volunteered to do it too, and Chie sees Yuuko as a bright spot of light in that moment.
The story skips ahead to October. Chie and Yuuko have been spending most of their time together. Another girl comments on how much the two of them have been sticking together, and Yuuko tells her that she gets to monopolize Chie because they're on the committee together.
Chie thinks to herself about the petite, straight line of Yuuko's back, and Yuuko's silky hair. She feels something "special" about the fact that they call each other by their first names, without any honorifics, and that they hold hands.
Chie asks Yuuko if stuff like that bothers her, and if she's just a nuisance to her. Yuuko says no, and that everyone's just jealous that they became friends so quickly.
Chie thinks to herself that she's never had a friend like this before, because she's not good with people. She's grateful for their shared duty--otherwise she wouldn't have gotten the chance to spend time with Yuuko like this. But...
The joint festival is being held with the neighboring all-boys school. (Chie's school is an all-girls school.) It's a major event that's only held once every three years. Chie wishes it hadn't come up this year--if it hadn't, she and Yuuko might have been able to just have fun together.
Chie has to pick the songs for the last night of the festival, and Yuuko offers to help. Usually, the organizing committee isn't able to attend the last night's celebration, but one of the older students tells them that the teachers are going to pitch in, so they can go. Yuuko and one of the guys, Sakiyama, are really happy about this, and the other students tease them about it.
Later, Chie tells Yuuko that she can't stand Sakiyama. Yuuko says she thinks he's a good guy, and that Chie worries too much about gender--that everything is fun when you're with someone you enjoy spending time with.
Chie thinks to herself that she's scared Sakiyama will take her place.
Chie wonders who Yuuko enjoys spending time with. She doesn't want Yuuko to leave her.
The day of the festival has arrived, and Yuuko's worries have proved groundless so far. She hopes it will all just end without anything happening.
But she sees Yuuko talking to someone...
It's Sakiyama, and Yuuko's agreeing to meet with him on the last night of the festival.
Chie comes back to the room later, but when she sees Yuuko there, Chie says she has a headache and needs to go to the infirmary. Yuuko insists on going with her.
While they're in the infirmary, they hear the fireworks that signal the start of the final night's celebrations, and Chie asks Yuuko if Yuuko has to go; Yuuko says no. Chie thinks to herself that she's a coward. She comes clean and tells Yuuko everything--that she overheard Yuuko's conversation, that she lied about the headache, and that she didn't want Yuuko to go. Yuuko hugs her, and assures her that she's not going anywhere.
She tells Chie that there's nothing going on with Sakiyama--that he likes another girl, and he was just asking Yuuko to arrange things to give him and the girl some time alone that night. Chie protests that that wasn't what it looked like, and Yuuko explains that it was probably just that she identified with Sakiyama, because there was someone she'd always wanted to get close to as well, someone who didn't see her. Someone she'd always wanted to notice her.
So when Chie looked up at Yuuko that day in class, Yuuko was so glad. It was like light was shining just on them. "So I'm not going anywhere," she concludes. "I'm here because I want to be with you, Chie."
Chie thinks to herself, "So I wasn't the only one---......"
Sakiyama and the girl call to them from outside (it looks like things went well for them too), and Chie and Yuuko decide to join the party. They decide to go together... to the far side of the light. (Maybe this means they're going into that light they saw in that moment Yuuko volunteered for the committee. Either way, it's some sort of metaphor for them finding happiness together.)