As a Sacrificial Pawn, I'm Surrounded by Beautiful Older Sisters

After suffering a calamity, Xia Yi was stranded in the mortal realm with her brother. She thought her story was about working hard to cultivate, returning to the upper realm, and avenging their parents.

The goofy guy next door, who claimed he could see the future, told her that her brother was a heaven-defying hero with a harem of three thousand, while she was a minor character destined to die on his path to power.

That was when Xia Yi, the doomed extra, discovered that the beautiful older sister who came to rescue her was the head of the Heavenly Secrets Pavilion; the white-bearded old man who shared snacks with her was the chief priest of the Imperial Astronomical Bureau; and even the poor soul she met by the roadside was a post-apocalyptic powerhouse hiding in plain sight.

Most importantly, why were all three thousand members of her brother's harem surrounding her? She was just a minor character, okay?!