On her very first day at Satogahama Municipal High School, Arihara Tsubasa steps onto the stage while the school's clubs are being introduced and declares, "The girls' hardball baseball team is looking for members!" Since it was originally a girls-only school, Satogahama doesn't even have a baseball team for boys. Tsubasa is scolded for making this declaration about a club that doesn't exist, but at her homeroom teacher's suggestion, she decides to start an association. Later, Nozaki Yuuki, a new student who can't decide which club to join, runs into Ukita Akane, who says she's looking for the girls' baseball club...
To start a new association requires five members... but the main thing the girls need in order to play baseball is a place to practice! But there are no suitable locations at the school for playing baseball. Tsubasa and the others are worried, but they tell themselves that all they can do is start with whatever is possible right now. They start by visiting a baseball shop to buy equipment. As they're picking out gloves, they realize that Suzuki Waka, a classmate of Tsubasa and Yuuki's, is also at the shop.
With a field, an advisor, and five members, the girls' baseball association is officially in action! They finally begin to practice using the training regimens devised by Waka... and as they do, second-year student Iwaki Yoshimi of Satogahama's cheer squad pays them a visit. Then another second-year, Asada Aoi, also shows up, and the two of them end up becoming members of the association! The girls are thrilled to add two unique new members to their ranks, And what's more, Nakano Ayaka of the newspaper club shows up, as well...
The semifinal round of last year's Senior Little League tournament came down to Fujiura High versus Kuramoto Chuo High. Recalling that game is vexing for Ryou, but to Tsubasa, it's a precious memory. Tsubasa opens up to the other members about why she decided to start a girls' baseball team at Satogahama instead of joining a club team. One year ago, Tsubasa was facing the decision of whether to keep playing baseball or quit.
With the addition of Ryou, the club now has nine members, so Tsubasa suggests that they play a practice game against another school. The Sato High Baseball Association is newly formed, so they have little chance of winning, but the members are happy to finally have a chance to play.
ハチナイ声優陣とハライチ岩井・とにかく明るい安村でお送りする特別番組。これをみればハチナイの魅力にハマってしまうこと間違いなし／鋭意制作中のアニメ新作の情報も！ 詳細情報 番組内容 アニメ「八月のシンデレラナイン」がもっと楽しくなる特別授業！ メインキャスト陣とハライチ岩井・とにかく明るい安村がアニメ「八月のシンデレラナイン」について振り返ります。 クイズあり、ゲームあり、さらに鋭意制作中のアニメ第１３話の新情報も！ これをみればハチナイの魅力にどっぷりハマってしまうこと間違いなし！ 出演① 【出演】 西田望見（有原翼役） 近藤玲奈（東雲龍役） 南早紀（野崎夕姫役） 井上ほの花（河北智恵役） 楠木ともり（小鳥遊柚役） 岩井勇気（ハライチ） とにかく明るい安村 出演② 【ナレーション】 中村繪里子（掛橋桃子役）
