Cursed Spirit

Cursed Spirits (呪い Noroi) are the manifestation and aggregate of negative energy leaked by Humans.

Overview
Cursed Spirits are born from juryoku from non shamans. As a result of the cursed energy flowing into particular notions or things, cursed spirits are born (sometimes referred to as curses).

These Curses are immune to conventional weaponry, cannot be seen by normal people unless under very specific cases and are only able to he harmed by Spiritual/Magical Energy known by the name of Juryoku (cursed energy/power). A lot of leaked energy in a particular area (such as schools or hospitals where large crowds gather) will cause the birth of a curse.

Most weak curses attach to a person, and cause them great discomfort (i.e. heavy shoulder, trouble breathing, nightmares).

The more negative energy used to manifest a curse (i.e. the longer there has been negative emotions towards a curse and more juryoku has consequently been directed towards it), the more powerful the curse is. Strong curses are also more human like; becoming bipedal, and with intellect that of a human. It is alleged that as they have had such a large amount of juryoku directed towards them, this has caused their sentience and driven them into hiding.

Where this energy gathers, a cursed object may be born as a talisman of that curse (eg sukuna’s finger). This cursed object may initially deflect other curses, particularly as the more negative energy or ‘curse’ applied to it; but where it’s seal weakens over the years, it will change forms and begin to attract curses and feed on them.

Curses allegedly tend to linger at their point of origin.

High Grade Imagined Apparition
Frightening imagery shared among many people manifests into powerful curses. Mythological creatures from stories can manifest, and become High Grade Imagined Apparition, where a significant of juryoku is directed towards them. The juryoku directed towards the forest, solid earth, the ocean, and other humans has resulted in the formation of High Grade Imagined Apparitions developing.