The Transparent World

Having glimpsed the Transparent World, Tanjiro finds his perception and speed sharply heightened, able to predict and dodge Akaza's blows while seeing his own breathing, blood and contracting muscles. He concludes that by shutting off his fighting spirit, he may finally be able to behead the demon. Meanwhile a desperate Giyu attacks with Water Breathing's tenth form but suffers a shoulder wound for only a shallow cut on Akaza's neck.

Akaza shatters Giyu's blade with his fist and prepares to finish him, only for Tanjiro to slice off the demon's hand and intervene. Sensing the changed slayer, Akaza grows alarmed and unleashes his final form, a sweeping omnidirectional barrage of explosive shockwaves. Giyu is gravely wounded surviving it, while Tanjiro, moving inside the Transparent World, slips entirely beyond the demon's perception.

The fight between Tanjiro, Giyu and Akaza continues to its turning point. Tanjiro enters the Transparent World and the Selfless State. With Akaza unable to sense him because his fighting spirit has gone silent, Tanjiro lands Hinokami Kagura: Setting Sun Transformation and severs the head of Upper Rank Three, shocking both Akaza and Giyu.

The chapter dramatizes the payoff of Tanjuro's lesson from the previous installment, with Akaza repeatedly failing to detect an opponent whose killing intent has vanished. Akaza even offers to turn the battered Giyu into a demon mid-fight, urging him not to die. The beheading lands precisely because Akaza waits for a fighting spirit that is no longer there. The chapter opens Volume 18 and belongs to the Infinity Castle Arc.