Appears in the story "The Case of Yui and Saori". Saori is Yui's childhood friend, though she secretly considers her bossy and selfish. She was interested in pursuing Endou but Yui got her to give up by implying that he was above her station. Saori intentionally steals the notebook from Yui and places it in her and Reiko's shared locker, knowing that Reiko would likely pick it up and cause trouble for Yui. In the end, Saori is the one whom Endou confesses to, as she had eaten the "E" mermaid's flesh before letting Yui and Reiko know that she'd caught one — the confession is, however, tainted by Endou admitting that he'd had feelings for Asami.