Yūichi Nekota, a newly enrolled first-year student at "Private Eucalyptus Leaf Academy," contemplates which club to join when he encounters mysterious quizzes and a peculiar beautiful girl. Her name is Chitose Arigasaki, who introduces herself as the president of the "After School Secret Club." It seems their mission is to unravel the hidden mysteries of the academy. Feeling unable to leave it alone, Nekota quickly decides to join, embarking on a club activity seeking the truth and kicking off their unique duo club journey.