Kofune Ushio

Ushio is the deuteragonist of the series. She is the daughter of Alan, sister of Mio, and adoptive sister of Shinpei. [spoiler]Ushio holds feelings for her childhood friend, and adoptive brother, Shinpei.[/spoiler] [spoiler]In the original timeline, Ushio was strangled to death when she tried to save Shiori from Shiori's shadow, together with Ushio's own shadow.[/spoiler] (Source: MANGA Plus)