Life Fibers

Life Fiber (生命戦維) is the material used in the production of Goku Uniforms and Kamuis. One-Star Goku Uniforms are composed of 10% Life Fibers; Two-Star Uniforms, 20% and Three-Star Uniforms, 30%. Kamuis are made entirely of Life Fibers. Hōka Inumuta is in charge of analyzing the Goku Uniforms researched by the Sewing Club.

In at least one occasion, experiments have been conducted by the Sewing Club, having a No-Star student wear a prototype Five-Star Goku Uniform. However, this caused him to become a huge muscular hulk and made him go berserk. Hōka Inumuta was able to restrain him.

This demonstrates that certain people have a greater control over Life Fiber based clothing. Ryūko Matoi and Satsuki Kiryūin are such people, both being able to wear and control Kamuis.

The name "Life Fiber" can be interpreted literally, since all Kamuis so far have been shown to be sentient, and at least Senketsu has shown intelligence on par with a human's.

Banshi
The Banshi (絆糸) is a vital thread of Life Fiber present in every clothing made with Life Fiber. It is what holds them together, since it is, according to Shirō Iori, imbued with the will to become clothing. It is protected by several layers of Life Fibers, making it nearly impossible to be located or damaged. If it is severed or removed, the garment is destroyed. Kamuis are shown to have multiple Banshi.