The Kamo clan is one of the biggest Jujutsu sorcerer families in Jujutsu Kaisen. They are called GOSANKE (big three) and have a long history and great influence from the Heian period to the current day. Each family has confronted the other and has never been on good terms.
What’s the Heian period?
It’s from 794 to 1185, the age of aristocracy in Japan. The Kamo family is descended from yin-yang masters in this era.
Yin-Yang Master Really Existed in Japan
A yin-yang master is called ONMYOJI in Japanese. The Onmyoji was a legitimate post of the ancient Japanese government and handled fortune telling, astronomy, and the calendar.
The Kamo family really existed in the Heian period and was the leader of ying-yang masters. I think the Kamo clan in JJK came from them!
In Japanese animations and mangas, an Onmyoji is often described as a Japanese-style sorcerer who employs familiar spirits called SHIKIGAMI, casts ying-yang spells, and fights against Yokai monsters. The most famous Onmyoji in real Japanese history is Abe no Seimei, and he learned the ying-yang technique from the Kamo family.
Kamo Clan’s Cursed Technique
The Kamo family controls their blood with the cursed technique called SEKKETSU SOJUTSU (Blood Manipulation). The kanji symbols clearly stand for their nature.
SEK = red
KETSU = blood
SO = control, manipulate
JUTSU = technique, skill, spell
Blood Manipulation allows a user to control blood both inside and outside his/her body. A user can change the shape, solidity, and even composition of his/her blood. It works only for a user’s own blood and can’t manipulate others’ blood.