The focal point of the manga of the same name, she aims to restore the demon realm by bearing a child of apocalyptic power.
The 10, 000-year old demon and heir of the Demon realm. This realm is not an actual dimension parallel to Earth, rather, Heaven & Hell are simply territories on Earth classified as such depending on whether they are angel or demon territory. However, her father the Demon King lost most of Hell's territory due to the angel's trickery, and now the "Demon Realm" consists of a ramen restaurant, run by Lucia and her father(her mother having left due to the Demon king's failures).
One day, Lucia's father overheard a young man as he revealed that his date & time of birth lined up as a perfect line of sixes. According to prophecy, the child of a demon and a human male with this fated time of birth would be a creature of world-ending power. Dreaming of using the child to restore his lost kingdom to its future glory, the Demon King sent Lucia to seduce this boy, Yuta Koizumi & bear his child, an order Lucia reluctantly set out to complete.
Lucia is the title character of Seo Kouji's Princess Lucia manga which began publication in the Magazine Monthly Comic blade in 2009. There is currently no available information about her inspiration or any of the other factors in her creation or development.
Lucia appears as a quite short & slender young woman with long red hair and some inhuman attributes. She has large curved horns protruding from her head and a tail comprised of chain links with a blade at the end. She can also manifest bat-like wings when she needs to fly. Her demon's appendages aren't visible to normal human beings.
Lucia has a temper and fury befitting that of a demon, and easily gets worked up. She is prone to abusing her powers when angered, however she rarely does anything excessively malicious and can show mercy when she feels the need to.
Despite her having lived for thousands of years, she is rather immature and prone to emotional outbursts which aren't limited to being angry. She often sulks, behaves selfishly or can be moved to tears without much effort. Although Lucia is a demon and often seems ferocious, she isn't truly wicked at her core, and the malevolence aspect of her nature is actually quite shallow.
Having been sent to mate with Yuta for the sake of bearing an all-powerful offspring, Lucia has come to develop sincere feelings for him. While he unanimously refused to create a child with her, Yuta instead offered Lucia his friendship as he perceived her loneliness and some of the good in her. As they spent more time with each other, Lucia began to fall for him.
Two angels were dispatched to guard over Yuta to ensure that he would have no contact with demons in his life. While these two are ostensibly Lucias enemies, they have developed an odd friendship with her, and actively try to hide her existence from the higher-ups in Heaven. Lucia regards the more senior and gentle of the two angels, Rie as a pervert as she is a rival for Yuta's affections. The other angel El has a brash personality, and she and Lucia frequently clash.
Lucia is a demon of exceptional power, even amongst other supernatural beings. She has a range of various destructive abilities at her disposal, including explosive eye beams, the ability to summon a massive primordial rock, and the ability to project a fearsome atmosphere that can bring lesser supernatural beings to their knees. She is also capable of sustained light, and her tail is fully-prehensile and can be used to grasp or cut objects. Lucia's body is also exceptionally resilient to physical or magical attacks.