As a high school student, Chiko possesses the unique ability to perceive the red threads connecting individuals to their soulmates. Acting as a musubi-ya, she utilizes these skills to offer counsel to her peers regarding their romantic endeavors in exchange for compensation. However, her discovery of a concealed chamber within the school leads her to encounter a peculiar white spool of thread, which ensnares her in a sudden and alarming manner. After awakening, she realizes her form has regressed to that of a ten-year-old child, and the only solution for restoring her original self requires employing the newly acquired thread to vanquish malicious entities and transform into a bona fide musubi-ya.
