Yae Sakura used to be the shrine maiden of Yae Village. Despite her devotion, hard work, and wishes for the village's well-being, her ill sister was ultimately sacrificed and used in a ritual to hopefully quell the Honkai. The ritual did not work and despite her sister’s last wish, she gradually began to feel hatred towards the village.

Four years after Rin's death, Yae Sakura grew up and honed her swordsmanship and became a hermit in the village, holding herself responsible for the sacrifice staying away from the villagers. Although still gentle and kind, the shadow of Rin's death stands true in her heart.

One day, Sakura finds a bleeding woman who's clutching a cracked black box to her chest. Sakura nursed the woman (Kallen Kaslana) back to health. The two quickly fell in love with one another. They both felt at home for the first time in their lives. But their happiness didn't last. The black box Kallen had with her actually contained the 12th Herrscher of the Previous Era, and it set its sights on Sakura. It managed to leak out through the crack and take advantage of Sakura's grief-stricken mind to corrupt her. Kallen reluctantly fights her possessed lover, and Sakura fights back against the Herrscher to give her an opening. Kallen takes it, and has no choice but to seal Sakura in the black box along with the Herrscher.

JPN Voice Reference: https://www.youtube.com/watch?v=5DblRzpxz-U

CN Voice Reference (Pink hair, Yae Miko): https://www.youtube.com/watch?v=bqUgOz5hsbg