The ritual was actually a trap for Yamime to steal the souls of the girls, and erase them from existence. After Satsuki discovers the plan, Yamime appears at her house while her father and brother are asleep to attack her. Satsuki consults the Ghost Diary and is told to "bind her with red string and bathe her in sunlight." Satsuki finds she has no red string and instead draws red lines with lipstick on her closet mirror in place of string so when Yamime looks into it it appears as if she were tied up. To 'bathe her in sunlight' she uses a camera flash. The next day, the girls who had been erased returned.
It is revealed that Shinobu was a classmate of Satsuki's mother who had gone missing under mysterious circumstances.