Luciana is small for a paladin, barely five-and-a-half feet tall, which causes some people to doubt her profession (an opinion not helped by her other features). Such doubts tend to die off when they see her in action.
When expecting combat, she keeps her long, dark hair tied back and tucked down between her armour and white hooded cloak to make it hard for enemies to grab ahold of and to keep it out of her eyes. She also considers her eyes to be her best feature (at least the best feature of her face); the left one is a pale blue while the right is a brilliant green. While demon-blooded tieflings tend to get very angry at people pointing out the asymetrical feature all such tieflings have, Luciana has grown to like the look. The rest of her face is almost stereotypically-Chelish - thin eyebrows and a narrow jaw as well as translucent, pale skin.
Her demonic features are relatively minor - a pair of small fangs, a pair of tiny horns poking up through her hair and a long, black tail emerging from the base of her spine. The tail is surprisingly thin along its length before flaring out into a spade-shaped head on the end about the size of her palm.
Her armour is predominantly functional; a suit of effective armour that still looks good is too far beyond her budget at this point so she makes do with an unflattering breastplate that gets the job done.
When not expecting combat, her clothing is very different - she's got a killer figure and knows it. Short skirts or minimal shorts to best show off her long legs and sleeveless tops to show the hints of muscle in her shoulders and arms (the muscles themselves aren't noticable unless she's flexing them, but she still has the slightly-broader-than-normal shoulders such strength usually accompanies). She also leaves her hair loose, where it hangs to just above her tailbone.
She's well aware that dressing like this is why she's gotten a lot of unwanted male attention - who tend to pay more attention to how well she fills out her shirt than how developed her arms and legs are, though they tend to realise the latter should things get to the point where they start losing teeth. Regardless of what she's wearing, she always has a symbol of Lymnieris hanging from a thin chain around her neck or on her belt.
Luciana is very laid-back for a paladin. She is also something of an incorrigible flirt, hitting on just about any attractive woman she meets. She has had her fair share of 'lady-friends' in the last few years and managed to perfectly balance such activities with her vows as a paladin of Lymnieris - taking precautions against disease, being entirely honest with these women and ensuring they do not believe the relationship is anything more than a one-night stand or a short-term, casual fling. And, of course, never letting such relationships get in the way of her greater duty as a paladin. It is a fine line to walk, but she has managed it so far.
Despite her womanising, she never 'kisses and tells'. If she ever references a past lover, she will either stick to things outside of the bedroom, or make oblique references and not mention the lady's name or other identifying features, often keeping the latter to people she hasn't been with in months.
While her training has certainly helped manage it, she still has something of a temper, though the spiteful nature she had as a child has passed (unless she can indulge in such vengeance without breaking her vows, in which case she may enjoy it a bit too much). Mostly it just results in snarky and sarcastic comments when annoyed enough. Fortunatly, it's rare that she stays annoyed long enough that these get too harsh but people pushing her too much are likely to get either the rough side of her tongue or the business end of her fist.
Even with this flaw, she takes her duty as a paladin more seriously than anything else. She worked hard to become a paladin and she would never jeopardise it if it can be helped.
A common misconception in Golarion is that paladins take a vow of chastity. In truth, this is a rarity and there are plenty of paladins who are either married or are at least in devoted relationships. Rarer are the paladins who have learnt to balance their vows and duties with their... amorous pursuits. Promiscuity is not directly forbidden by most paladin orders but the vows normally make such behaviour more difficult as misleading a partner can risk a fall. Luciana is one such paladin.
Born and raised in Kenabres, Luciana was something of a pain as a child. She had a tendency to break the toys of other kids who angered her and was, in short, just a pain in the neck. When she was ten, she was kidnapped by cultists of one demon or another - she was too young to remember exactly which one - and forced into a strange ritual. She was equal parts terrified and angry when her part in it came up but was as curious as the cultists when it seemed the ritual failed. She'd felt the energy enter her, but all it did was temporarily make her strong enough to break her bonds and escape (accompanied with a well-timed use of her magical ability to shatter glass).
The experience left her with a deep hatred of demon cults (moreso than what most Mendevians harbour) and a strong desire to strike back at them and hopefully put whatever demonic taint she absorbed to a greater use. She worked to become a paladin but her rage held back her training in an Iomedan order. When she was sixteen, she met a travelling priest of Lymnieris who managed to teach her to let go of her anger. Many who know of him forget Lymnieris is as much a patron of those undergoing rites of passage, official or otherwise, as he is of willing prostitutes and the priest saw Luciana's becoming a paladin as such a rite of passage.
The priest told her of a small order of Lymnierisan paladins in Nerosyan and Luciana saw this as her last chance at her dream. With her parents' aid, she went to Mendev's capital and joined the order, refusing to leave until she became a paladin. Three years later, she succeeded and was ordained as a full Paladin of Lymnieris whereupon she returned to Kenabres, hoping to protect her home city from any future cults like the one that kidnapped her.
Unlike the avatar picture, Luci doesn't have that dark stuff around her eyes.