Leader of House Nogi, a traditional rival to House Tokai.
House Nogi's ancestral seat is in Petal Bay.
He seems to also be generally being used as an anti-Takanata political force. It's not clear he's a bad guy per se, and the King has asked Takanata not to start a House War, so don't jump him very hard, but we probably don't want him prospering.
A Buddy Told Li Merit
He's in his mid fifties, and has been Lord Nogi for about fifteen years. The first ten years, he was kind of on autopilot, but in the past five years or so he seems to have gotten his act together more, and since the islands switched positions, he seems to have found dealing with this to be (depending on how cynical you want to be) his opportunity, or his purpose.
He has several wives and a larger handful of children; his wives seem to be neither Perfect Political Alliances nor Grand Romances, but something in between - attractive and not-unsuitable partners. He might have made better matches had he been trying, but he could certainly have made worse. He does have an eye for attractive women, and has had several discreet mistresses as well (Shuyan is on this list as a "possible").
He has been friends with Su Song since the Imperial Cartographer came to live in the Isle of Beauty, and there's some indication that Su helped encourage him towards the "Save the Island from its Northernishness!" crusade, definitely including the Petal Bay fortifications, but to all indications, the crusade itself is sincere.
Nogi's own character is mixed. He is reasonably smart, but thinks he is smarter than that. He is a not-bad judge of character, but thinks he is a good judge of character. He tends to look for ulterior motives, but he seems to be sincere in his Petal Bay project, rather than having the obvious ulterior motive of "because it's good PR for my House". He feuds with Tokai because it's the thing House Nogi does; he's doing it more than back when he was on autopilot, but he doesn't seem to think Tokai is evil or anything like that.
Xiao Fa Thinks
He's definitely making a power play for his house (and the rivalry with House Tokai is sort of an automatic part of that), but it's not a destructive power play. He seems to have gone after the Important Person Niche of "someone needs to make sure we prosper in this new location" - it's a thing that needs doing if the island doesn't move back, and tying his fortune to doing that successfully is kind of a risk. (It also means if House Tokai gets the credit for swapping the islands back, that will swat Nogi down pretty hard). I do not believe he is trying to keep the island in its new place, only deal with the island being in its new place.
If there is a way to have Nogi and Tokai reconcile, thereby weakening Su Song's influence on the Isle, that would be a thing Xiao Fa would like to see happen.