Aoi Yusa/Plot Overviews

Background
Aoi Yusa is a student of St. Chronica's Academy from class 2-3, the same class as Sena's. Seeing Sena Kashiwazaki as her contender, Aoi hopes to outperform Sena in all areas, be it intelligence and athletics. Unfortunately, as diligent as she is, Aoi would usually end up in second place before Sena, much to her nuisance. Despite this, her skills have made her suitable to become her school's Student Council treasurer.

Filming
In one of the bulletin boards on their campus, Aoi looks on at the rankings for the finals. Shortly thereafter, Kodaka walks into the same bulletin board and finds Aoi angrily looking at the rankings. Afterward, Aoi notices Kodaka and immediately mistook him as Sena's rumored boyfriend. Not knowing who the girl is, Aoi becomes frustrated and introduces herself in front of Kodaka. Knowing her place in the rankings and in the Student Council, Kodaka compliments her, which only adds oil to the fire as Aoi continuously complains about her lack of abilities to outperform Sena but at the same time praising her, despite Kodaka reassuring Aoi. After trying to clarify to her that he and Sena are not dating, Kodaka becomes shocked after being told by Aoi that he is "cool" and fashionable. Afterward, Aoi leaves while Kodaka is being moved by Aoi's words.

School Festival
Prior to their school festival, Sena and Aoi had an argument over who will run the relay for their class during the festival. The position was handed down to Sena instead.

During the athletics festival, Aoi is one of Hinata Hidaka's aides and possibly one of the staff members handling the events. Likewise, she is also represented as one of the participants of class 3.

The following day during their cultural festival, Aoi again acts as one of the staff maintaining the order around the campus. During her duty, she founds a student taking down posters in one of the school's bulletin boards, which reveals to be Kodaka. After apologizing to him for shouting at him, Aoi learns that Kodaka and Sena are fellow club-mates after Kodaka clarifies to her that he is not Sena's boyfriend. Aoi then constantly ask questions regarding about Neighbor's Club goals and activities, and after having known about it, Aoi leaves bidding farewell and luck to Kodaka for the success of upholding their club's ideals.

Crisis within the Neighbor's Club
After monitoring the Neighbor's Club for a week, Aoi intrudes into its club-room. After having a short argument with Sena, Aoi declares her business in the club-room; complaining about the Neighbor's Club's lax atmosphere. While Aoi claims that all the club does is "laze around", Yozora Mikazuki corrects her by saying that they're only taking a break from the festival. However, Aoi holds nothing back as she declares that she's from the Student Council and has the right to submit requests of disbanding clubs. Meanwhile, Yozora defends her claim that the Neighbor's Club is a legitimate club that hasn't done any wrong by relating the activities and games they tackled as steps into realizing their club's goal: being able to become good neighbor's to their fellow students. After being told that her opinions have no right in criticizing club activities, Aoi points at Yukimura Kusunoki, Rika Shiguma and Kobato Hasegawa. Claiming that the three latter girls to be breaking school regulations of not wearing their respective uniforms, Yozora again nullifies her claim by stating that their actions of not wearing uniforms are allowed when or during club activities. Afterward, Aoi focuses on Kobato, a middle schooler, to be disallowed from entering school premises. However, Yozora defends Kobato's membership to the club by stating that Kobato remains as a student of St. Chronica's and that the chapel - where their club-room is located - is actually an establishment for public use despite being on school grounds. After declaring that Kobato is a legitimate member of the Neighbor's Club, Aoi storms off the club-room.

Aoi again returns to the Neighbor's Club clubroom the following day. Aoi shocks the club as she declares that their club moderator, Maria Takayama isn't actually a sister working in the academy, an information she uses for club's immediate disbandment. However, Sena, who had seemingly ignored Aoi's presence from the start, cuts off Aoi and walks out the clubroom. Meanwhile, Kodaka has Yukimura serve Aoi some coffee, as Yukimura regrets not poisoning Aoi through the cup of coffee she just served. But thanks to Kodaka's cover-up, Aoi mistook Yukimura's intention as a joke. Moments later, Sena returns to the clubroom and declares that Maria has been appointed as the club's temporary lecturer after calling his father, much to Maria's excitement. Albeit saving the club from disbandment, Aoi expresses her protest until Sena threatens her from being expelled from the academy. With this, Aoi apologizes in front of the Neighbor's Club as she promises to never bother again before leaving.

Days later, after skipping a week from her duty as treasurer, Aoi solely does her work by carrying, transferring then organizing boxes filled with printouts from the school festival. As she does this, Aoi stumbles on Kodaka. Though avoiding him, Kodaka offers to help Aoi in carrying the boxes. As they were, Kodaka asks Aoi why she's so determined in disbanding the Neighbor's Club. As an answer to his question, Aoi states that a person with great talent shouldn't waste their potential while referring to Sena. Afterward, Aoi tells Kodaka that her claim of breaking up the Neighbor's Club for Sena's benefit was a lie, adding that she only did it out of her envy for the latter and for the sake of fairness. After apologizing to Kodaka, the latter reassures Aoi by reciting the one thing Sena doesn't have: friends. Upon hearing this, Aoi bursts into laughter, mistaking Kodaka's claim as a joke as she states that no one is friendless. Afterward, Aoi thank Kodaka for cheering her up.

After organizing the boxes they carried at a storehouse outside the school building, Aoi thank Kodaka for his help as she told him to return to his club. However, Kodaka continues to offer Aoi his assistance going as far as to skip club activities. With it, Aoi accepts Kodaka's offer of lending her a hand. After the back and forth, Aoi and Kodaka were halfway into finishing the grunt work as Aoi states to Kodaka the reason why the Council still holds campfires during school festival despite its drawbacks. After agreeing on doing the remaining ones the next day instead, Hinata Hidaka, the Student Council President appears before Aoi and Hinata. After introducing themselves to one another, Hinata mistook Kodaka as Aoi's boyfriend. After denying the claim of their senior, Aoi asks Kodaka why he hasn't dated someone in the Neighbor's Club. Though not coming up with a straight answer, Aoi states that it would be too awkward if Kodaka had dated someone inside the Neighbor's Club. Consequently, Kodaka patted Aoi on the head in agreement. Meanwhile, Hinata offers to help in Kodaka and Aoi's work, despite the latter trying to brush Hinata off. Nonetheless, Aoi agrees.

After finishing the grunt work, Hinata asks Kodaka to enter the Student Council, much to Aoi's surprise. However, Aoi is also siding with Hinata of having Kodaka a part of the Council. Though despite this, Kodaka reveals to the two the bad reputation he has in school and the treatment he receives from the students. Afterward, Kodaka promises to help the Student Council in any type of labor despite not being a member of the Council itself.

A week later, while tagging along with Kodaka in delivering some paperwork, the duo stumbles on Kodaka's fellow female club-mate, Yukimura Kusunoki. Aoi and Yukimura have a heated argument after Yukimura badmouths the Council. Aoi then recognizes Yukimura as the person who intends to poison her a week before, which Yukimura agrees. Bewildered by Yukimura's attire, Aoi questions Yukimura why she is wearing a boy's uniform. Despite knowing that the latter is Yukimura's way of 'becoming a true man', Aoi calls Yukimura weird. Angered by Aoi's words, Yukimura made a scowl at Aoi as the two glare at each other in animosity. As a result, Kodaka has Aoi going ahead of him as he converses with Yukimura, and Aoi reluctantly agrees.