Erulu, a young dragonkin mage from Dragon Village in Gaeabrande, is the childhood friend of dragonkin warrior Mash and daughter of the revered Great Mother of Dragons, guardian of the village and the legendary demon-slaying sword Igzasion.

Her path crosses Seiya Ryuuguuin and Ristarte during their mission to save Gaeabrande. After Mash's rescue from Deathmagla's torture, Erulu joins Seiya's party alongside Mash, primarily serving as one of Seiya's equipment carriers due to his demand for excessive backup gear. Initially an offensive mage, her abilities shift towards support magic under fire goddess Hestiaca's guidance, focusing on healing and spells to enhance the party.

A critical moment arises when the party seeks Igzasion in Dragon Village. Erulu's mother reveals forging the sword requires a dragonkin soul sacrifice. Erulu volunteers her life for the world's salvation. Seiya intervenes, defeating the Great Mother and rejecting the sacrifice, preserving Erulu's life and strengthening her resolve to support the party through other means.

Her bond with Mash remains constant, marked by mutual concern. Her dynamic with Seiya involves exasperation at his extreme caution, yet she benefits from his protective actions, like his choice to save her over acquiring Igzasion, implicitly valuing her beyond utility.

An alternate "Bad Future" timeline, where Seiya and Ristarte never intervened, shows Mash as the hero sacrificing Erulu for Igzasion. This corrupted ritual traps her aware soul within the sword, driving her toward madness and vengeance while Mash descends into tyranny, highlighting the tragedy avoided by Seiya's actions.

Following Gaeabrande's salvation, Erulu continues aiding the party on subsequent missions, including the journey to Ixphoria, cementing her role as a dedicated support member.