In 2019, Yashio Kaito and Senomiya Akiho have been lifelong pals and are completing their final year in high school. They are both members of the robotics club, which has lost its financial support and currently has two members left. Akiho is devoted to the world of robots and wants to fulfill her sister's unfinished project. While Kaito is not particularly interested in robotics, he remains in the club out of loyalty to Akiho, as his attention is mainly focused on his preferred online game "Kill Ballad Online." However, when Kaito is accused of cheating in the game, Akiho boldly decides to find funding for her sister's enormous robotic creation to save the club from disbandment.
