The episode opens with the final moments of Rui, the Lower Rank Five demon.
As he disintegrates, Rui realizes his parents actually intended to die with him out of love. Tanjiro, sensing his grief, shows mercy by placing a hand on his back. In the afterlife, Rui reunites with his parents, who promise to stay with him even in hell. Conflict Within the Corps
During their standoff, Shinobu famously teases Giyu, stating that nobody likes him—a moment fans often cite as a series highlight. Kimetsu no Yaiba Episode 21
The rest of the team—Inosuke and Zenitsu—are rescued and sent for treatment at the Butterfly Mansion.
The episode ends with a bound Tanjiro waking up at the Demon Slayer Headquarters, surrounded by the elite Hashira. Demon Slayer: Kimetsu no Yaiba Episode 21 Review The episode opens with the final moments of
Rui was born with a frail body that left him unable to walk or go outside. Muzan Kibutsuji appeared and "saved" him by turning him into a demon, giving him a powerful body at the cost of consuming humans.
, titled "Against Corps Rules," serves as the emotional conclusion to the Natagumo Mountain Arc, balancing a tragic villain backstory with high-stakes tension between the Hashira . Rui’s Tragic Backstory In the afterlife, Rui reunites with his parents,
When his parents discovered his monstrous nature, they attempted a murder-suicide to stop his sins. In a rage, Rui killed them, believing their bond was fake.