Demon Slayer: The Sky Hashira

Youmu Lin's parents were killed by a demon. When she was on the brink of death, she was saved by young Uta and Yoriichi Tsugikuni. She thought she could have a new family, but that same demon struck again, killing Uta and her unborn child. From then on, Youmu set out on the path of demon slaying.

She has awakened all three abilities: the Transparent World, the Demon Slayer Mark, and the Bright Red Nichirin Sword. She has also mastered Spatial Breathing and every original Breathing Style.

Unfortunately, she failed to kill Muzan. She sealed herself away, waiting for a child of destiny capable of slaying Muzan to appear and break the seal. She will devote everything to the cause of demon slaying, including her life.

(To be clear, there is no romance in this story. The heroine and Yoriichi Tsugikuni are just siblings, with nothing romantic between them. When she awakens in Tanjiro's generation, she will not have a romance with anyone either. Her only goal is to slay demons.)