Naka ga Warusugiru Osananajimi ga, Ore ga 5-nen Ijou Hamatteiru FPS Game no Friend datta Ken ni Tsuite.

"If I become stronger than you, then you'll stay with me forever, right?" Shintaro is the number-one ranked player in the world for a popular FPS. When he decided to enter the national tournament with the goal to become a pro gamer, he found out that 2N, the second-ranked player and his dual partner, turns out to be his estranged childhood friend Natsuki!? (Source: Hifumi Shobo, translated)