"A Disturbing Freshman" is the eighteenth chapter in Ahiru no Sora.
The name of the troublesome freshman is Kenji Natsume, also known as Tobi. After witnessing Yasuhara's beat down, Nabe, Chucky, and Sora also decide to join the minor scuffle. The outcome of the brawl remained the same. Momoharu approaches and instructs them to stop the fighting; Kenji, annoyed by Momoharu's decision, tries to kick him. Hanazono, to halt his kick headbutts, and informs Natsume that he will not fight back. A frustrated and angry Kenji walks away.
After Kenji's departure, Momoharu then asks his colleagues what happened. Yasuhara responds that they saw Natsume practice at the outside basketball school's court. He approached Kenji to praise him for his efficient basketball skills, and suddenly, he started hitting him. Afterward, in the boys' locker room, Momoharu tells his teammates that he had a meeting with their schools' advisor, and they cannot afford to get into any fights. Yasuhara informs what if that freshman, Kenji shows up in the schools' gym and decided to join their team. Momoharu responded that he would deny his entry into the club.
While heading towards their basketball gym, Momoharu and his teammates see Kenji dribbling on the court. They are astonished and shocked to see him. Kenji recklessly drives passes all the girls' team members. Sora tries to stop him and informs Natsume that the boys' team cannot practice on the court, and currently, is being used and occupied by the girls' basketball team. Kenji doesn't listen and does a crossover move on Sora. While going for a layup, he knocks down one of the girls' team member. She passes out, and everyone in the gym goes into panic mode.