In 2026, four years after the infamous Sword Art Online incident, a revolutionary new form of technology has emerged: the Augma, a device that utilizes an Augmented Reality system. Unlike the Virtual Reality of the NerveGear and the Amusphere, it is perfectly safe and allows players to use it while they are conscious, creating an instant hit on the market. The most popular application for the Augma is the game Ordinal Scale, which immerses players in a fantasy role-playing game with player rankings and rewards. Following the new craze, Kirito's friends dive into the game, and despite his reservations about the system, Kirito eventually joins them. While at first it appears to be just fun and games, they soon find out that the game is not all that it seems...

Hikaru Tsutsui is a high school student. He enjoys animation and video games in the virtual world, but he doesn't enjoy his real life. People at his school don't even know he exists. One day, he cleans up the pool at his school with beautiful Iroha Ikarashi. Iroha approaches Hikaru and confesses that she likes him.

Tsutsui Hikari (a.k.a "Tsuttsun") is a high school student who is content with his virtual life of anime and video games. One day, he gets stuck cleaning the pool with Iroha, a real live girl who is stylish, sassy and known to be easy with boys ... and she aggressively approaches him! Tsuttsun, who has few friends and lives in his own world, finds himself smitten by the confident and wild Iroha ... and his whole world is turned upside down!! It's the awkward and pure love story of a boy who experiences relationship for the first time.