Lazy and pragmatic, but takes incidents seriously. Even as people's memories fade, she feels a strong sense of wrongness regarding the traces of what was lost. She investigates alongside Marisa, but eventually realizes that her own memories are also missing pieces.

Cheerful, bold, and full of curiosity. While gathering evidence of the incident, she discerns that the disappearances are not mere memory loss. She harbors a single secret she cannot tell Reimu. From the middle of the story, anomalies begin to appear in her very existence.

Even when stopping time, she cannot observe the voids created by the incident. She discovers that an old clock in the Scarlet Devil Mansion is ticking at a time that shouldn't exist.

Sensitive to the presence of ghosts and spiritual anomalies. She is shaken by the phenomenon where even the souls of the vanished cannot be found. She notices her half-phantom constantly facing a direction where no one is present.

Yukari Yakumo. She seems to know about the incident in Gensokyo but does not tell Reimu and the others everything. Beyond the boundaries, she has discovered a darkness that should not exist in Gensokyo.