Shingo Komoi

He uses a Murakumo deck based around the Magatsu ride chain. Shingo is first shown as seemingly a stalker to Kourin. Naoki notices this and threatens to beat him up for stalking Kourin but then Shingo suggests they have a cardfight instead. It is later shown in the episode that his idol is actually Aichi as Shingo became a fan of Q4 when he saw Aichi compete in the VF Circuit. Source: Cardfight Vanguard Wikia