Sara Vazelia reigned as princess of the Kingdom of Vazelia, celebrated across the land as its most beautiful woman and adored by her subjects. A Horror's attack left her face horrifically disfigured and shattered her sanity. Consumed by shame over her appearance, she incinerated the entire kingdom.

Dario Montoya, her assigned Makai Knight protector, blamed himself for failing to stop the Horror. Overcome by guilt, he gouged out his own eyes, abandoned the Makai Order, and devoted himself solely to her care. Unknown to them, Vazelia stood atop the sealed tomb of the legendary Horror Nigra Venus. The kingdom's destruction broke the seal, freeing Nigra Venus. The entity then possessed the despairing princess after she ended her life within Vazelia Lake.

As the vessel of Nigra Venus, Sara regained her flawless beauty, transforming into a deadly lure. To men near the lake, she manifested as a naked beauty, killing them with a kiss that froze victims solid before shattering their bodies and absorbing the remains. For female victims, she revealed a grotesque tongue-mouth within her face, latching onto them to tear away faces and frontal skulls. These acts birthed the local legend of the Demon of Vazelia Lake.

Nigra Venus acted to activate Zirkel's Ring, a mystical device crafted by the Makai Alchemist Mendoza. This required sacrificing Germán Luis's young son, Roberto, as a key. Activating the ring threatened to distort time and space by allowing souls devoured by Horrors to return from the Makai world. Ultimately, Nigra Venus was defeated in battle by León Luis, the Golden Knight Garo. Both the Horror and Dario Montoya met their end together in the lake's depths.