Tension
How tightly rope is applied in a tie, which holds its structure and shapes how it feels; in Japanese the loanword also names the emotional tension between partners.
Anatomie Studio calls tension one of the most important and most difficult parts of tying well: people in rope prefer different amounts, but some tension is needed to keep a tie’s structure, above all in suspension. Kinbakuwiki, giving the Japanese loanword tenshon (テンション), explains that adequate tension holds ropes and patterns in place, limits movement and creates a feeling of compression, while too much makes a tie uncomfortable and can restrict circulation. It contrasts styles: semenawa-oriented lineages such as Yagami-ryū tie with higher tension, while Yukimura-ryū uses looser rope and also treats tension as the emotional tension between the two partners. Shibari Study counts evening out tension as part of dressing rope.