he swordsmith Tōtōsai created the Tessaiga from a fang of the inu-daiyōkai, Tōga, the father of Inuyasha and Sesshōmaru for the purpose of protecting his human bride, Izayoi. In its 'docile' form, the sword looked like a regular (and rather battered) katana. When wielded properly, it transformed into a weapon roughly the size of a car bumper that somewhat resembles a falchion or, due to regional and historical context, a dadao sabre. As Tessaiga only transformed if the user cared for humans and had yōki, this means that while humans could never wield it in its true form because they do not possess yōki, it would still however protect a human wielder from deadly yōkai abilities. The Tessaiga had the power to slay 100 demons in one swing by striking the Wind Scar; it also had the ability to absorb the technique or skill of a strong yōkai that was defeated with the sword.