Lord Minoru Katsu is a young man in the Minoru family, one of the three ruling families of the Shrouded Isle. He's probably going to be the next Firelord. The Minoru and Suzuki families have a marriage contract engaging him to Lady Suzuki Kuan-Xi. Kuan-Xi finds both him personally and the prospect of royal life in general stifling, has been unsuccessful in convincing her mother that she should not wed him, and has fled from the situation. Katsu doesn't appear to love Kuan-Xi, but takes his family obligations seriously and thinks she should as well. He hired goons to try and capture her, but they were thwarted by the party. As of The Eighth Name he thinks she has been abducted by ninjas and is trying to find and save her.
His Aspect is Dog. See General Horoscopes for more astrological details.
Yoshi's Analysis (just after The Eighth Name)
Katsu maintains a thin veneer of politeness over intense pride. He has a high opinion of himself, and convinces himself that it is justified even if he engages in conduct that he condemns in others (e.g. seeking to kidnap Kuan-Xi). He is polite, but far from diplomatic. His attitude towards the party is that it is pointless to try to justify himself to friends of Lady Suzuki.
When dealing with him, it is important to keep in mind that he is in a very difficult situation: the Minoru and Suzuki families created a marriage contract that Kuan-Xi is disregarding. Evidently this will dishonor both families, him personally, and result in her being disowned. As far as I can tell, he had no role in creating this situation (except perhaps that he was not to Kuan-Xi's liking). He believes that the marriage contract would justify him in abducting Kuan-Xi and forcing her to marry him, though he has pangs of conscience about this course. He is affronted by what he sees as Kuan-Xi's childish flight from her responsibilities, and her disrespect for him and their families.
I believe I have persuaded Katsu, at least temporarily, that attempting to coerce Kuan-Xi is inappropriate (and doomed to fail). However, he is still pursuing her at least to free her from ninjas. It is not clear to me what he would do next if he learned that she had not in fact been kidnapped.
Unrelated to Kuan-Xi, as soon as I mentioned that there was widespread suffering on the Shrouded Isle he warned me quite vehemently against treasonous talk, for it was not appropriate to speak of insurrection. Since I had not mentioned insurrection, I assume it came to his mind because he has been hearing such things often from other people. I did not probe him on the issue.