The soul of A (Ace) that is passed down―― May the youth of the armed detective girls be eternal!! Shino, who learns the joy of being loved more than loving, decides to study abroad in Germany……. The strict "traditions" of the Mamiya family force Akari to move to Ibaraki. However, the bonds of the girls who have overcome numerous hardships cannot be broken by anyone! The youth story of the first-year armed detective students, finally reaching a grand finale of love and emotion――!!