Cardfight!! Vanguard (2011) : 3x1

Months after the conclusion of the VF Circuit, Aichi enters high school as a freshman at Miyaji Academy. However, he has trouble adjusting to his new school life due to the academy's heavy emphasis on studies. After school, Aichi goes to Card Capital while being tailed by a classmate, Naoki Ishida. There, he sees the many customers playing Vanguard, which Naoki has no knowledge about. He spots Aichi conversing with Team SIT Genius in the back of the shop. Curious by how different Aichi's behavior is in the card shop compared to how he acts at school because of a card game, Naoki becomes intrigued to Vanguard. And so, Aichi teaches Naoki about Vanguard through playing an actual match, with the latter being lent a new Narukami trial deck to use from Shin. As they cardfight, Naoki slowly gets immersed into the game. After Aichi eventually wins, Naoki buys the trial deck and hastily leaves in a frustrated manner, which worries Aichi.