Yūshū Yūdaina. That's family name first, folks.
Yuushuu, Yuudaina, or Yuushuu Yuudaina. He tends to replace the macrons with two "u"s, as they just complicate things a lot of the time.
For generations, the Yuushuu family have had significant holdings in Loguetown - whilst not particularly concerned with matters of populace there, their funds have been quite extraordinary, and those who have been given the opportunity to marry into the family have rarely failed to leap at the chance. Such a marriage, whilst largely love-driven, was essentially what first united Yuushuu Saidou and his wife, the woman who would eventually rename herself Kireina. Some years later, their first child was born, and named Yuushuu Yuudaina.
As is often the case with one's first child, they made a few slipups here and there in raising him, leading his personality to be a bit separate from their worldviews. In this case, that might have been a good thing, for as with many Nobles, Saidou and Kireina were both rather nasty people, keeping slaves for their own personal gain and generally hoarding anything they wanted, whereas Yuudaina was a bit more in touch with others, desiring more to see what else lay in town, though not quite grasping what made his parent's slavekeeping so immoral. Such is childhood, though; the Yuushuu's next two children, Suguremashita and Sugureta, were kept on much tighter leashes and indoctrinated far more thoroughly, but Yuudaina was nonetheless in line to lead the Yuushuu household after his parents eventually passed.
Yuudaina was about twelve when his parents brought in a different slave. A white-haired, purple-eyed child, one who had apparently been born into slavery, and yet who was deliberately kept separate from the other slaves, never visibly joining in with their work for the Yuushuus. At about the same time, two major events happened: Saidou and Kireina's relationship began decaying almost immediately, and the Battler first showed his face on their property, apparently linked to the new slave's role in the household.
Whilst the slave didn't exactly make much of an impression on Yuudaina at the time, he was practically smitten with how powerful the Battler seemed to be when showing off his combat skills, and begged the man to teach him how to be that strong. The Battler explained that whilst he couldn't tell Yuudaina everything, he could certainly tell him some things, which might make him very powerful indeed some day. And so, for the next several years, as much of Yuudaina's free time was spent with the Battler as possible. He learned boxing in various styles from the man, amongst other forms of unarmed combat, as well as how to utilise something called Life Return, eventually allowing him to concentrate his senses and control the most minute aspects of his physique, from his hair to his muscles.
He had only recently turned eighteen when he learned, overhearing an argument, precisely why his parent's relationship had been decaying for so long, why his formerly-beautiful mother had begun to... swell, was the best word for it. It turned out that the slave that had been brought in many years ago was not intended for hard labour. He was intended for use as a sex toy by Saidou, once his wife was past her best, an arguably self-fulfilling prophecy considering her reaction to his intent to cheat on her. Worse still, the Battler, who Yuudaina had looked up to for a great many years, was in on this - he was there not because Yuudaina wanted him to be, but because Saidou paid him to guard the slaves, and in particular to essentially brutalise the white-haired slave, so as to recondition his mind to better accept his eventual nature as a pervert's plaything.
Naturally, he was disgusted with his father for the whole scheme, disappointed with his mother for falling into her own well of despair instead of putting a stop to it, and utterly disillusioned by the horrifying nature behind what may as well as have been his hero throughout his teenage years. He argued with his family, harsh words were said that could not be taken back, and he ultimately stormed out of the house, intent on joining the Marines as soon as possible. Coincidentally, his sister Suguremashita left the household that same day, despite her comparative youth at the time, with the described intent of becoming a merchant in some form or another, to travel the seas and become wealthy without relying on her parent's money. To his knowledge, she has been relatively successful so far, though he hasn't heard much from her other than that she visited the Yuushuu mansion recently to pick up a particular slave for her own use.
Yuushuu's entrance into the Marines was at the level of Chore Boy, much like many other Marines. He did not stay at that level very long, displaying a combination of raw power and ingenuity that bumped him up to the level of Master Chief Petty Officer within three years, which he felt wasn't a bad start considering he'd largely been patrolling the weakest sea, the East Blue. Even then, his impression of piracy in general was very poor, and was set to become much worse very quickly: around that time, on a mission to help save the Gecko Islands from being ravaged by a massive pirate raid, he met a woman called Alicia Vale. She had been rendered the victim of a severed limb by the invaders, amongst various other physically-damaging indecencies, then left for dead, and she had been left in severe shock as a result, with mental trauma sure to follow; roused to great vengeance and furious anger, Yuudaina brought her into Marine care, then turned around and slaughtered as many of the pirates as he could, an event which would finally elevate him to Warrant Officer after a few months of stalling.
Little did he know how much of an impact he would have on the woman's life, nor she on his. Following a severe crackdown on pirate activity in the East Blue in response to the attack, almost a year without many incidents led Yuudaina to see Alicia more and more frequently, to help her through her issues (by teaching her the Life Return ability, amongst other things, to see if she might be able to regrow the lost limb), and in time to realise that she was really quite a wonderful woman underneath the events that had scarred her so. In time, they found themselves falling in love with one another, and ultimately they married, Alicia bearing a child who would eventually be named Francis. As close as they were, Yuudaina had deliberately never introduced her to his family; eventually, though, he bit the bullet, and asked her to move to Loguetown, to which she agreed. As it happened, he had business with his family as well.
The slave was still being trained by the Battler. He took a wide berth around both of them whenever he could. Sugureta was beginning to act up more and more lately, a sign that perhaps his parents were not the greatest at raising kids. And the parents themselves... were surprisingly willing to show contrition for their earlier arguments. Though Yuudaina was rather upset and horrified at how his mother's figure had turned near-spherical by this point, and still all but enraged by the continuing progress of indoctrination on the now-teenaged slave, she and his father not only blessed his impromptu marriage unconditionally (verbally, at least), but also promised to acquire the funds to build Alicia a new robotic arm to replace the one she'd lost, and furthermore presented him with a huge shape-shifting sword, "a weapon worthy of a newly commissioned officer- oh, did we forget to mention we've paid for you to head through officer training? Be sure to send us some money back from your cushy job!" He did wonder how much of this had to do with Sugureta's lack of suitability as the face of the Yuushuu family in the future, but not one to reject sudden charity, Yuudaina accepted the odd gifts and the implication, however forced on their part, that he was back in line to inherit most of their wealth once they passed.
His training to become an Ensign was not particularly overbearing, and included an expanded patrol into the South Blue as well as the East Blue; but from then on, advancement would become increasingly difficult, with a solid two years between Ensign and Lieutenant Junior Grade, and another two from there to Lieutenant proper, and frequently decreasing timeframes in which he could see his beloved again, though with that in mind, he began practicing with Life Return in an effort to figure out agelessness and eternal youth for himself, and likewise encouraged Alicia to do the same, that they might spend eternity together once all else was said and done.
He was around twenty seven when he heard the bad news: Saidou had finally tried to make good on his plan to turn the white-haired boy into a pleasure slave, only to wind up dead by the slave's own hand. Worse still, Sugureta had just days before stolen a vast quantity of the Yuushuu fortune, spending it on what Yuudaina had learned was called a Devil Fruit- the same power fueling his weapon's shapeshifting ability, as it happened- then fired the Battler by pretending his father had no further use for him, causing a ruckus during which the white-haired slave stole the Devil Fruit and escaped Loguetown entirely as a member of another pirate's crew. They weren't entirely broken as Nobility, and Kireina claimed they would recover in time, but they'd lost their patriarch and more than ninety-five percent of their wealth in that fiasco, with his brother the perpetrator now nowhere to be found. Naturally, Yuudaina was given leave to visit his grieving mother- who it turned out had been grieving for her dead husband for more than a month by the time he made his way home.
Not that that stopped her from making rather bad decisions for Yuudaina. Apparently, though they were already strapped for cash, Kireina had bribed the Marines to essentially put in a good word for Yuudaina and get him moved to a position in the Grand Line, "because wouldn't that just be such a good legacy for our family to follow, my son working in the Grand Line?" Alas, Yuudaina suspected that whoever had handled the arrangements had had a cruel streak of irony in them, since supposedly, the bribe hadn't been sufficient to place Yuudaina anywhere in the Grand Line but one of its worst bases: Marine Grand Line 5th Branch, a.k.a. G-5, well-known for its troublemakers and upstarts, and located in the New World no less. Though he felt he might be a tad unprepared for such a posting, Yuudaina nevertheless approached the impromptu lifestyle change with gusto, and though comparatively new there, he has managed to get himself installed as the 2nd Patrol Unit's Master-at-Arms, making it his duty to better the base with his presence no matter its reputation.