Having the chance to read a post from each of you, I have decided to re-write Hiroyuki's views on them. I feel a lot happier with these descriptions. I am also finally writing out the possibilities of which directions these relationships could go. Better late than never, ne?
As far as romance goes, there are very, very slim chances for anyone with him. Frankly, he does not know what romance is, nor real love. Lust, on the other hand... Due to being aware that he does not understand the emotions in himself or others very well, he accepts this fact, and feels no remorse or loss over the topic. It would not be efficient nor logical for him to attempt crossing that line, as it would likely lead to confusion and distraction, things he does not feel he can afford to have. That being said, if a particularly stubborn and patient person was persistent, they may get under his shell and open up a glimmer of hope. Maybe.
Nishi-san- Having listened to night after night of stories and babble from the man, he has formed a sort of fascination with Norisane. This is caused by not only his obvious gaijin heritage, but the life he has. Having been tucked away in a small corner of the county most of his life, Hiro finds the accounts of travel and adventure appealing in a way he cannot quite explain; perhaps a yearning, or even envy. There are still constant annoyances, such as Norisane's drinking and stubbornness, but these things help fuel the frequent, friendly duels the two engage in. The only thing that may cause a fight between them is the issue of forgiveness. Hiroyuki sees Norisane as soft and wistful for believing that everyone deserves a second chance. Of course, there is also the issue of Norisane's fondness of sake- should it ever inhibit his ability to serve Kanegawa, Hiroyuki would be one of the first to call him on it and issue a punishment.
If Norisane should prove that he can, indeed, set a rational line which forgiveness cannot be given, Hiroyuki's overall respect for him would increase. As well, should his drinking be limited to when it is considered socially appropriate, his overall respect and fondness would grow. Another thing that would raise his opinion is if Norisane actually defeats him in a duel. Should he do something foolish, such as allowing himself to get sloppy due to drinking or his soft heart, Hiro would regard him as lesser; wasting his skills and unfit for his duty.
Suda-san- Due to her quiet and reserved nature, Hiroyuki is very comfortable with Yurie, though not very close. They both like to have their silence and distance, and they give it to each other without complaint or feeling the need to "connect" as people typically do. There is a certain mute agreement they seem to have, and that is enough. Unlike many others, he holds no judgement over her in regards to her gender or appearance. Instead, he forms his opinions based solely on her skills, which he admires for their sly artistry and beauty. However, he is very much aware that her skills are not honed by true battle or war, which does cause him to regard her as lesser than himself. Her youth is not something she can control, but it does cause inexperience, which he recognises as causing potential problems. Overall, he sees her skill set as being unique and valuable, even if they are not wholly refined.
So long as she continues to hone her skills and work to make them more practical, Hiroyuki's opinion of her would not lower. However, in the event that her youth and inexperience should cause her to make poor decisions, he would not be very tolerant.
Kikuichi-san- With a level mind that is sharp as a blade, Kirihime is highly respected by Hiroyuki. Her martial prowess combined with cunning tactics on the battlefield impresses him, though he is keenly aware that the strategy she uses causes emotional strife. This makes him uneasy and disappointed from time to time, as he does not see the point in getting so upset over gender bias and social pressure. He sees her inflicting pain and stress upon herself in a rather paradoxical way, and cannot help but wonder as to why she bothers giving in to her clan's wishes when it causes so much distress. Despite all of this, he cannot help but give a nod of recognition toward how far she has come through the face of adversity. This tenacity, combined with skill and intelligence, causes Hiro to admire her and would regard her as a friend, if he knew what a friend should be.
Due to already regarding her so highly, there is not much room for his opinion of her to raise. However, should she ever overcome her obvious social pressure and gender conformity issues, he would regard her as much stronger and wiser. Should she fully cave in to this struggle, he would most certainly think of her as weak. There is also the issue of her anger- should she let it get the best of her, he would look down on her.
Yoshanai-san- There is a plethora of reasons as to why Hiroyuki does not like this man. His paranoid beliefs and mental instability make him and obvious wildcard in Kanegawa's hand, and Hiro wonders if he could actually be controlled, should his inner demons attempt to break free. Aside from this, clashing beliefs and modes of thinking causes altercations between the two. Kaze is one of the few things that stir strong emotion within Hiro, and it is not a pleasant one. He finds him to be honourless and honestly wonders how the man was able to be called samurai at all. If he had his way, Kaze would never have been accepted into the guard. There are too many unpredictable factors involved for him to be reliable and trustworthy.
There is nothing Kaze could do that would heighten Hiro's opinion of him, aside from a miraculous change of heart and personality. Should Kaze do anything to cause doubt regarding his capabilities as a samurai, his sanity or morality, Hiroyuki would gladly end his employment, one way or another.
...Wow, that got long- sorry!