Jujutsu Kaisen takes anime fans to a different world where all living things are capable of emanating energy called Cursed Energy. This energy comes from negative emotions. Since human beings are living things, they have cursed energy too but normal people cannot control it. When a normal person loses cursed energy, it results in curses.
These are spiritual beings that wanted to bring harm to humans. They look like gruesome monsters that normal people cannot see or touch. The only ones who can perceive cursed spirits are sorcerers. Each cursed spirit has a unique shape and size. They can possess an item or inanimate objects. Lastly, cursed spirits have grades that determine their level of cursed energy.
Like jujutsu sorcerers, cursed spirits are ranked as well but the classifications are not entirely exact. Each sorcerer can take down the curse of the same level or lower. There are different ranks: Grade 4, Grade 3, Semi-Grade 2, Grade 2, Semi-Grade 1, Grade 1, Special Grade 1, and Special Grade.
Usually, curses that are under Grade 4 are easily beaten by inexperienced sorcerers. Grade 3 level curses can be beaten by average sorcerers like students. Those that are in Grade 2 are above-average curses that needed to be exorcised by sorcerers that are at the same level.
Semi-Grade 1 cursed spirits are considered a danger on special occasions. These curses are powerful and have the ability to communicate. The only way to extract these curses is by using Suguru’s Cursed Manipulation as Semi-Grade 1 curses are expected to utilize cursed techniques.
For special grade cursed spirits, only 16 were confirmed. These are usually feared by sorcerers and are regarded as Imaginary Vengeful Spirits. One best example is Sukuna, the King of Curses.
After Sukuna was reincarnated or had Yuji as his vessel, there are unregistered special grade spirits that appeared. Unregistered means that the university does not have any records of these. Some examples are the Mahito, Jogo, and Hanami, among others.
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