Webwe learn that giyu and sabito, the ghost boy who trained tanjiro at the beginning of the series, were best friends and learned together under the former water.
Webbreathing at resonance frequency (rf, approximately 6 breaths/min) constitutes a key part of hrvb training and is hypothesized to be a pathway through.
Webfurthermore, the analysis of tanjirou’s journey leads to a revelation of the inner transformation that he experiences, which is the positive change arc, and thus, making.