The original 'Shakugan no Shana' light novel series, written by Yashichiro Takahashi and illustrated by Noizi Ito, began publication.
The first season of the 'Shakugan no Shana' anime adaptation aired, boosting the franchise's popularity.
The second season of the 'Shakugan no Shana' anime series, titled 'Shakugan no Shana Second,' aired on television.
The third and final season of the anime, titled 'Shakugan no Shana Final,' was broadcast.
The 'Shakugan no Shana' light novel series concluded with its 22nd volume, wrapping up the original story.
The manga adaptation of 'Shakugan no Shana' was serialized, extending the franchise's reach in print media.
The formation of the Crimson Realm and emergence of Crimson Denizens, including the initial concept of Flame Hazes and Bal Masqué.
The ongoing balance between the Crimson Realm and the Human World is established, with Flame Hazes appointed to maintain equilibrium by consuming the existence of Denizens who feed on human 'powers of existence'.
Yuji Sakai is born, destined to become the 'Mystes' whose existence is central to the plot as a Torch and a key to the balance between realms.
Yuji encounters Alastor, the Flame of Heaven, who burns Yuji's existence and marks him as a Torch, setting the events of the series into motion.
Shana, a Flame Haze contracted to protect the human world from Denizens, meets Yuji to guard over his life and deals with Alastor’s connection to him.
Shana and Yuji combat Denizens invading the human world in Misaki Town, introducing the central conflict of Denizens feeding on humans' powers of existence leading to flame haze intervention.
The secretive organization Bal Masqué's deeper involvement in manipulating world events and powers of existence, including their leader Margery Daw's agenda, is revealed.
Yuji confronts the existential crisis of being a Torch, having lost his true existence but continuing life as a 'mystes' tied to Alastor, which challenges his humanity and relationships.
The decisive battle involving Shana, Yuji, and allies against the Bal Masqué's conspirators such as Hecate, determining the fate of the human world and Crimson Realm.
After the battles, a new equilibrium is achieved between the worlds, with Shana and Yuji continuing their lives while preserving the fragile peace.
