Lust

Lust is one of the Seven Sins, the set of sin-grimoires that also includes Pride (Superbia). She manifests her power through sexual stimulation: no man can resist her enthralling beauty, and her mere presence is enough to enslave the will of an entire empire. Her two core 'functions' are sexual desire and mind control; unlike Pride she has no combat ability or regeneration of her own, and this in the end becomes her undoing.

Lust's purpose of existence is to 'give birth' to a perfect being. Like Pride she strives toward the same absolute, but by a different method: where Pride seeks it through her own body, Lust seeks to bear it. She births children who surpass their parents and for centuries practices incest among her own descendants, creating monsters beyond their species. She is, in essence, an incubator for whom her own children are merely a string of 'attempts and failures,' cornerstones of the final being to come; she feels no maternal emotion. For a thousand years her genes have dissolved into the people of the eastern continent, and her 'failed creations' gave rise to ancient races — Ulfheonar, Arva, Vulcans.

On the eastern continent Lust secretly rules an empire under the human name Sim Samho, holding the whole imperial family — her own descendants — in her grip. When a fall in mana concentration threatens to ruin her design, she launches the 'Heaven Demon' project: to birth a single being capable of being reborn as a great god even in other dimensions, she triggers a large-scale mutation of the entire eastern continent, turning it into a factory of 'materials.' This makes her a direct threat to the whole material world and Theodore's principal foe in the eastern arc.

During the war Lust personally appears at Hyeongan Castle and abducts Sylvia, seeing in her some special significance unknown even to Theodore and a 'perfect vessel.' Veronica nearly becomes her slave and is saved only by the 'bond' — her contract with Theodore that shields her soul. Theodore conducts grim negotiations with Lust for Sylvia's freedom and prepares a trap in advance: under the guise of a deal he implants the spell 'Mutual Destruction' into her 'seed.' When the heaven demon she bore is defeated, the spell triggers; bereft of combat function and regeneration, burned and torn apart, Lust cannot heal — her skin dries like plaster and she crumbles to pieces, irreversibly, before Theodore.

Lust subjugates her victims through irresistible sexual desire: no man can withstand her beauty, and a single glance is enough to turn a person into a puppet. Even Theodore is blinded by her sensuality, and Sylvia — and nearly Veronica — fall under her spell. Only those whose soul is already bound to another can resist, like Veronica, whose contract with Theodore admits none of the grimoire's mystic force.

Yet unlike Pride, Lust has neither direct combat ability nor regeneration. Pride would heal any wound instantly; Lust cannot. Pierced by a Magic Rocket, she merely keeps talking but cannot mend herself. It is precisely this vulnerability that makes her end irreversible: when Theodore's trap triggers, the grimoire's burned and torn body dries out and crumbles to pieces.

Lust is an 'incubator': she births offspring stronger than their parents and for centuries practices incest within her bloodline to breed the absolute hybrid. Power is no goal for her but a means: she seizes a power base (an entire eastern empire whose ruling family are her children) so she can pursue her purpose of existence in peace. Her many 'failed creations' over a thousand years gave rise to ancient races — Ulfheonar, Arva, Vulcans.

'Heaven Demon' is the name not of a being but of a project. Realizing her potential in this dimension is nearly spent, Lust pours all her resources into birthing a single being able to be reborn as a great god in other dimensions. The large-scale mutation of the eastern continent is merely the supply of 'materials' for it. Even a deliberately flawed heaven demon yields data to adjust her main body. Theodore destroys both the heaven demon and Lust herself, cutting off her entire design.