The news of Kourin transferring into Aichi's class becomes a hot topic, especially when the male classmates start talking to Aichi to get closer to her once they learn that the two know each other. Then, Aichi gets an idea on how to promote Vanguard at his school. Because there is no Cardfight Club, Aichi decides to make one himself. The next day, he tries to recruit enough members to officially start the club (needing a minimum of five people, including himself) by handing out leaflets in front of the school. His pleas fall on deaf ears until Kourin agrees to be a member. Her enlistment is followed by several other boys who want to join (only to be with Kourin), but she proposes that anybody who wants to become club members will have to defeat either her and Aichi in cardfights before they can enter. The two easily beat all of the challengers, but then Naoki steps up to play against Kourin with honest feelings of wanting to join the club.
With a new Jewel Knight Royal Paladin deck, Kourin battles Naoki, who uses the Eradicator Narukami trial deck he bought a while ago. In the middle of the fight, Naoki reveals that he knew Aichi from when he was in the elementary school division of Miyaji Academy and how he felt guilty for not doing anything to help Aichi who was being bullied at the time. Naoki further explains that seeing how much Aichi has changed because of Vanguard motivated him to find something to be passionate about and ultimately change himself. In the end, Naoki defeats Kourin with the Break Ride ability of Eradicator, Vowing Sword Dragon. With that, Naoki is initiated into the newly-formed Cardfight Club, and Aichi's life in high school truly begins.