While traveling toward Sagiri Mountain, Tanjiro passes through a small town and purchases materials to make a basket to carry Nezuko in. He leaves the town at sunset when Nezuko is able to walk beside him.
The siblings eventually pass by a temple with the lights still on. Tanjiro wants to see if anyone is there, but immediately notices the scent of blood.
Tanjiro rushes to the temple's entrance believing that someone might have gotten hurt along the path. He opens the door and is shocked to find a Demon feeding on two dead men. Annoyed, the Demon turns to the Kamado siblings and warns them about trespassing on his turf. The Demon turns to face them and, as the last light whithers away, he pounces on Tanjiro.
Tanjiro quickly reacts by drawing his hatchet and slashes open the Demon's throat. The man-eating Demon stumbles back, but it only takes a few seconds before the "scratch" is fully healed. Nezuko meanwhile, is distracted by the bloodied victim's bodies.
The Demon pins down Tanjiro before he has time to react. Tanjiro's enemy easily overpowers him in strength and speed. The Demon tries to snap the boy's neck but Nezuko comes to her senses and rushes back to her brother's side. She kicks the Demon's head clean off his body, freaking out Tanjiro.
The Demon's body slowly tries to grab Tanjiro so Nezuko kicks it away into a tree. The Demon's head and body can move individually. The body attacks first, serving to isolate Nezuko from her sibling. Tanjiro tries to help, but the Demon's head grows arms and he leaps onto Tanjiro's hatchet. The body kicks Nezuko several times before throwing her deep into the forest.
Tanjiro headbutts the Demon with reckless abandonment and it proves effective. The Demon suffers two blows Tanjiro's rock hard head before getting thrown with the hatchet into a tree, pinning him there. Tanjiro tracks his sister to a cliff side where she's being kicked closer to the edge.
Tanjiro tackles the Demon's body over the large cliff, but Nezuko grabs him before he falls too far. The Demon's body falls to its demise, and the head is knocked unconscious as a result.
Tanjiro prepares a knife to finish off the Demon's head. He's struggling to come to terms with taking another life and believes this isn't the Demon who attacked his family. A man in a goblin mask appears and tells Tanjiro he can't finish a Demon off using a simple knife.
The masked man challenges Tanjiro to figure out another way. The boy believes crushing the Demon's head with a rock will suffice, but can't bring himself to brutally end the creature. The Demon awakens and curses Tanjiro until the sun rises and he disintegrates into ash.
The man introduces himself as Sakonji Urokodaki. He believes Tanjiro will never cut it as a Demon Slayer. Tanjiro is unable to make decisions and can't even answer a question about the potential danger his sister presents to humans. Even so, Sakonji agrees to test the boy's capabilities.