In the process of investigating Director Shindou's murder, Nishinosono and Saikawa learn the details of Shiki's multiple personalities and the murder of her parents that took place 15 years ago. The two of them try to figure out what she was thinking in order to find a clue.  In doing so, Nishinosono is forced to confront her own past.
Yes, and that seven was the only lonely number.
.نعم، وذلك السبعة هو الرقم الوحيد المنعزل
Ja, und sie sagte auch,
dass nur die 7 einsam wäre.
Sí, y que el siete era el 
único número solitario.
Sí, y que el siete era el 
único número solitario.
Oui, et seul le 7
est un nombre solitaire.
Sì... e anche che il 7 è solitario.
Sim. E apenas o 7 
é um caso a parte.