I think the Patriarch's 3rd Wife fits best for Lucas, the last son of the last wife fits nicely. 
I was intending for Lucas to be about a year older than Vincent, so the timeline looks good to me.

I have also found a pair of suitable images.
[hider=Lucas Zeno Kaides]
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[hider=Images]
First, one that's pretty close to his current age, perhaps a bit too old but it gets the look across
[img]https://i.imgur.com/4pepv39.jpeg[/img]
Secondly an older version. 
[img]https://i.imgur.com/zvXrrBc.jpeg[/img]
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[h3][b][i]Lucas Zeno Kaides[/i][/b][/h3]
[b]Age:[/b] 15 [25] | [b]Height:6'[/b] | [b]Voice:Baritone[/b] 
[h3][i]First Life[/i][/h3]
Lucas was his mother's last child, a disappointment like all the rest. Lucas could never shake the bitter feeling that had he been born to a lesser family his lot in life would have been better, all his problems were the unreasonable expectations of the Kaides, he was smart, he worked hard, he listened to the instructors, but he lacked natural talent, every ounce of muscle the result of hours of excercise, every strike or block the result of constant practice. At first it wasn't so bad, he was treated rather kindly, tutors supportive of hard work, praising his occasional successes as often as critiquing his failures, childish games and stories often mixed between proper lessons. Around the age of 10 things changed, he was never told why, but an overheard conversation about spoiled half-siblings certainly gave him an idea. his instructors became stricter despite his best behaviour, and what scant praise he used to treasure dried up.

Collegem Yllustre was worse, the instructors seemed to have something against him, or perhaps it was his family for they were already being called a disappointing generation when he arrived. Even when he bested other students in the sparring grounds he received no praise, only a list of mistakes that a better opponent would have exploited to defeat him, there it was again, the unfair expectation that he somehow rise to perfection just to be worthy of the family name, apparently the failing of his (half-)siblings just made them more desperate for at least one success rather than buying him some breathing room. When he stayed up late to write careful essays on military tactics, history or natural philosophy, he received not a single word about what he did well, just red ink outlining every last little flaw. 

This began to make him bitter and unmotivated, why bother to try so hard if noone will ever be happy with him, he thought. And so he stopped trying so hard, at least not for them. He kept up most of his physical training, he may not be able to make the tutors or his family happy, but holding his own in the practice bouts is a more personal goal and hard as the work was, he did enjoy it. Other areas were allowed to slide, getting on the bare minimum of effort, why put work into lessons on leadership and tactics when his family will never allow a failure to command anyone, why focus on these odd anatomy studies that are only useful to those who will awaken their aura.  

He turns 21 in the year 1013 and leaves without graduating, a strong 1st rate guisarmier by the standards of most knights, but merely failure by the standards of House Kaides. By this point Lagentym has fallen, with soon to follow, so rather than being cast out on his own or sent somewhere quiet and out of the way where he could do no further harm to the family line, he's sent to the front lines. Luzia needs every able warrior more than House Kaides wants to hide its failures.  

He's initailly assigned to a batallion composed primarily of men-at-arms and lead by a knight from one of the vassal familiies. The fighting was worse than anyone had expected, despite their heavy armour they took serious casualties in every battle, mundane steel simply could not stand up to the brutal force behind an ogre's club. Things really went to hell when their leader was among the slain, there was no time to bring in a replacement from elsewhere and the men-at-arms were mere retainers to a vassal house, they had neither the tactical education nor the family name to lead, and thus Lucas was placed in command. Lucas who had given the last three years of tactical education only the most cursory of efforts, in a war that was seeing experienced commanders lose time and time again. Within a month the unit had suffered such severe casualties that it was deemed impractical to reinforce and the few survivors use to replenish other fighting forces. Lucas never received any formal reprimand or acknowledgement of his failure as a leader, what was one more fallen batallion among the many losses of this war, but he didn't need one, he had failed and there was noone to blame it on.  
The next year or so is something of a blur to him, he's blaming himself now, quietly of course, decorum is one thing he actually managed to learn, but that doesn't actually give him, but that doesn't make him any less bitter, doesn't bring back motivation. They march, they fight, they either win a temporary victory or once more retreat. Some of the other soldiers probably notice his generally miserable demeanor, but who among them has much to smile about. 
Things take a positive turn for Lucas, at least on a personal level, in 1015, another scrapping and restructuring of units as yet more of them fail, this time he's under the command of one Sir Justinian Lascaris, an older knight from one of the branch families, with an awakened aura and the charisma of a true leader, the kind of man who inspires his troops in battle, drinks with them afterwards and believes in fostering camaraderie among them. 
It's one of these post battle, half-drunk, bonding experiences where the topic of childhood and training comes up, as Lucas comisserates with one man's tale of early morning drills where every failed block got him smacked with a thick wooden training blade by recounting his own tutors and their relentless criticism that Sir Justinian interjects, to general agreement, that he'd have killed for that sort of detailed feedback on exactly where he was going wrong rather than simply being told to watch closer and practice more when he was trying to earn a knighthood, ending with the comment that kids these days don't know how easy they have it. The rest of the men don't really bring it up again, to them it's just onother conversation, memorable only in so far as Lucas usually doesn't have much specific to say, but he can't stop thinking about it, criticism is helpful? Other people would still want the life he was born to after learning what it actually means? 
The introspection does him some good, takes some of the bitterness away, brings back that drive to improve he'd practically forgotten, he even starts trying to make friends with some of the men and women fighting beside him.  
Of course there's still years of war left, it takes its toll the same as ever, comrades fall to the demons, but Lucas mourns them as friends taken too soon, rather than numbly pressing on. He even finds something more with a lady named Felicia a year younger than him with a knack for making him smile despite the world falling apart.  
Sleepless nights of constant watchfulness combine with thoughts of what he could have been had he only done better and the ever present sight of better warriors wielding their aura leads to strangely lucid dreams of what his own might be and in the final month of 1016 his own aura finally awakens.  
An awakened aura is certainly a boon, but he can never shake the feeling that it came too late, humanity's chances had been nosediving ever since Ylliastrum fell over a year ago.  
1017 comes, Kaidisyum falls, news comes that many of the tutors he once blamed for his own failures fell in battle delaying the demons, hard to hold a grudge against a man for his teaching style while one of the few refugees is describing his part in the diversion that let them escape.  
Felicia falls in battle mere weeks before Hadrum, the truly gut wrenching fact is that if Lucas had had just a little more stamina in his Aura, he's sure he could have slain the high orc that clove her in two.  
He joins the others gathering at Hadrum despite his ever growing misery, he has no intention of bording the escape ships, no he'll die delaying the demons, perhaps that might make him in death the Kaides he never quite managed to be in life.


[hider=5 useful questions, in bulllet point form]
[list][*]Biggest Failure: Two stand out, but they're so intermixed he'd struggle to pick: the constant, self-pitying need to blame every hardship on anything but himself, chiefly blaming his family's expectations and the poor reputation his siblings saddled the generation with, and how he allowed that bitter attitude to sap his motivation. There were other mistakes, but this is something he can, quite ironically though he may never see it that way, blame only himself for.  
[*]Biggest Regret: He wishes he'd not been too caught up in his pre-concieved notions of unfairness to see that the criticisms of his tutors were their way of telling him how to improve himself, that such a harsh attitude was not some personal torment, but a desperate attempt to see him realise his full potential rather than squander it as so many others had. Some of the blame certainly lies on the instructors and even his mother, who never thought to explain this to him, but he'll always wonder if perhaps he might have actually succeeded had he listened rather becoming ever more defensive. Maybe he still wouldn't have graduated, but would he have awoken his aura earlier, could that have made the difference in battle?
[*]Biggest Obstacle: Might skip this one, I like the idea of his biggest failing being his own attitude, rather than someone else.
[*]Greatest Achievement: An awakened aura and Felicia at his side were a brief bright spot in a miserable war.
[*]Driving Hope: Prior to the war it was less hope more resignation, he had no choice but to finish his time at the Collegem and hope whatever task the family had lined up for him wasn't too unpleasant. In the war it took many forms, at first he simply wanted to survive (fleeing never even occurred to him, whatever his flaws, he was never a coward). After his disastrous command he was decidedly unmotivated, beyond a vague idea that continuing to fight was the least he owed those he failed. Then came those he fought alongside, how could he let Sir Justinian down, hwo could he abandon his battle brothers, would life even be worth it if he wasn't fighting by Felicia's side. Finally, in those last miserable weeks was a mixture of spite and a reignited desire to finally live up to the family name, he would die with his weapon in his hand, spitting in the demons' eyes.[/list]
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[h3][i]Equipment[/i][/h3]
[list][*]Preferred Weapon:A Poleaxe
[*]N/A[/list]
[h3][i]Abilities[/i][/h3]
You have [b]4 Experience[/b] to spend here
[list][*]Physical Strength: 1st Rate (2 Exp)
[*]Aura: 1st Rate (2 Exp)
[*]Magic: 0th Circle 
[*]Skills:(None, but I'll leave the formating here)
[list][*]Skill/Spell Name - Skill/Spell Description [list][*]Sub-Sub-List for Upgrades.[/list][/list][/list]
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