Ichinawa 一縄
Free-form tying with a single rope, often a flowing scene that alternates binding and release.
Ichinawa (一縄) refers to tying with just one rope. Shibari Study describes it as free-form tying with a single rope that often develops into a fluid scene moving back and forth between binding and release, and relates it to ippon nawa shibari, bondage done with one rope. Rope365 lists ippon nawa (一本縄, one rope) alongside ichinawa, glosses ichinawa as “best rope”, and says the word mostly describes sensual tying, though it has other uses too. Shibari Study notes a debate over which of the two names is correct, since Japanese counts different kinds of objects differently, and accepts both.