Sakurazuka Natsuki

The Natsuki that Tsukumo finds alongside another... Tsukumo. In this temporality, Tsukumo ("Onii-san") managed to save Natsuki from her accident, however he finds himself in "double copy" in his temporality (present time). He then decides not to interact with them so as not to destroy the temporal flow (or something like that) but a fight between his other him, Natsuki (who loses consciousness) and thugs force him to intervene.

Being the same Natsuki that the player knows since the beginning of the game, she keeps all the attributes of her counterpart, just her role and her health state changes.
Seen only in the third chapter.