The target the brothers are ordered to watch. She was born on the same day that her sister Momoka died and believes that she is Momoka's reincarnation. The death of her sister caused her family to fall apart; her parents divorced and she lives with her busy mother. She possesses Momoka's diary, the entries of which she follows religiously for the purpose of "destiny". It is because of these entries that she stalks Keiju Tabuki, who was very close to Momoka. She believes that by replacing her sister, she will be able to bring her family back together. This includes fulfilling Momoka's wish to have children with her boyfriend.