Sabito and Makomo

The third anime installment, drawn from chapters 4 and 5, opens as Tanjiro keeps a journal for the sleeping Nezuko before his formal instruction starts. Sakonji Urokodaki lays out the nature of the Demon Slayer Corps, an unofficial yet ancient body of fighters, and describes how demons regenerate, shapeshift, and can only be slain by sunlight or a special blade. Across roughly a year of grueling drills, Tanjiro learns to read scents, dodge traps, swing correctly, and harness Total Concentration Breathing. When Urokodaki declares there is nothing left to teach, he sets a final challenge before vanishing.

The mountain trials

Tanjiro repeatedly climbs and descends Mount Sagiri, growing sharp enough to evade hidden snares laden with knives and spikes. Urokodaki drills sword forms, hardens his stamina, and explains how a blade cuts along its strong axis. Months pass while Nezuko remains asleep and a summoned doctor finds nothing wrong with her.

The boulder and the two strangers

Tasked with slicing a massive boulder, Tanjiro fails for half a year until a masked youth, Sabito, confronts him and beats him in spars. A gentle girl, Makomo, corrects his form and teaches him the true purpose of breathing. After six months together, Tanjiro defeats Sabito at last, and his swing splits the boulder as both spirits fade away.

The two eyecatchers reproduce the covers of chapters 4 and 6. The anime visualizes Tanjiro writing his journal, whereas the manga only references it during the time skip. His sword-swing count differs as well: the manga shows at least 716 repetitions, while the anime depicts a full thousand plus a demand for 500 more. His first attempt at cutting the boulder appears only in the adaptation.