The shimenawa is a special rope tied around or across an object or space to denote its sanctity or purity. “Shime” means hold or embrace, and “nawa” means rope. It is believed that this twisted rope keeps the impurity away from the kami's place, and is also a protect against evil spirits. Dark arts warriors and shadow warriors can all be identified by this rope, as it is worn around the neck for practical and spiritual protection. The dark arts warriors drape the shemagh scarf over there heads then anchor into position by using the Shimenawa Rope. Shadow warriors use this to banish evil spirits, identification as a Shadow Warrior to others, and to neck restrain challengers or prisoners during the shadow trial if required.
No matter which is the actual origin, they are undoubtedly thought to be the boundary between the sacred and the profane, used to ward off diseases and evils. When you see it around a tree a rock or the neck of a Shadow Warrior, that means it is a Yorishiro -- an object capable of attracting spirits called Kami. Never cut down such a tree, or challenge a Shadow Warrior in which is believed to be inhabited by spirits, because it’s thought to bring the misfortune or Death. This also is explains why a Shimenawa is used in Sumo Wrestling to denote the highest rank of sumo because Japanese people believe that the Yokozuna-- the highest rank of sumo is a living Yorishiro inhabited by a spirit.
The tenth symbol or character of choice on completing the ritual of the Kobudera or Kuji-no-In is written down on a small peace of paper as a Kanji and placed within the bow of the Shimenawa Rope to either summon or protect you when facing danger or within the throws of Battle.