Sasha Necron, daughter of Anos Voldigoad's creation Ivis Necron—one of the Seven Elder Demon Emperors—had her soul split at birth by Ivis's Dino Jixes spell. This division birthed Misha Necron as her younger twin sister, but bound Misha to cease existing on their fifteenth birthday during fusion, forging Sasha's core conflict.

Initially arrogant and haughty, she flaunted pride in her royal lineage and magical prowess, reacting with hostility to perceived underestimations—especially from Anos during early encounters. She commanded loyalty through leadership and strategic competence, coordinating complex spells like Jio Graze in battles. Her relationship with Misha remained distant and strained; she belittled her sister and denied their bond.

Her demonic heritage granted innate Magic Eyes of Destruction—initially difficult to control—and prodigious magic amplified after achieving a complete source. She wielded the Phoenix Mantle, crafted from divine bird feathers, enhancing fire magic, enabling wound recovery through magic, and offering immortality to the worthy while threatening to consume the unworthy.

A pivotal shift occurred in the Demon King Academy arc. Defeated by Anos when he countered Jio Graze with a basic fire spell, she reluctantly joined his team, sparking gradual respect. After Anos revealed Misha's desire for reconciliation, Sasha reconnected with her sister, thanking Anos with a "kiss between friends" that signaled growing trust and affection.

Driven by devotion to Misha, Sasha later stabbed her during a dungeon exam and stole the Phoenix Mantle—a desperate bid to save Misha from vanishing by swapping their fates via a spell requiring Misha's rejection. Misha’s refusal forced Anos to intervene. He deduced their shared origin and proposed fusing with past selves through time travel, rebirthing them as true twins without Misha’s demise. Overcoming opposition from Ivis Necron and the Guardian God of Time, Anos succeeded. The fusion ensured both sisters’ permanent survival, cementing their reconciled bond and mutual care.

Fully integrated into Anos's team, Sasha participated in events like the Magic Sword Tournament alongside allies such as Lay Glanzudlii and Misa Ilioroagu. She displayed a softer side, particularly toward Anos, where romantic feelings blended with deep loyalty. Training under him honed her abilities until he expressed confidence in her against any modern demon. Her development continued through arcs including the Demon Sword Tournament, Hero Academy, Great Spirit, and Selection Judgment, showcasing ongoing growth and evolving relationships.