After enduring several bizarre phenomena orchestrated by Heartseed, including body swapping and age manipulation, Taichi, Iori, Himeko, Yoshifumi, and Yui face a new challenge—emotion sickness. This mysterious affliction causes their emotions to transfer to others, leading to unexpected and dangerous consequences. As they grapple with fears and hidden feelings, the group must unravel Heartseed's latest scheme, forcing them to confront their innermost secrets and vulnerabilities.