Intriguing world-building. Neumeier always creates fascinating fantasy landscapes and, even more important, believable societies to inhabit them: given the constraints of this landscape and these laws of physics/magic, what society would work to deal with them? Tuyo is set in a world divided by climate: the vast, snow-bound, moon-ruled winter lands and the gentle, fertile, sun-ruled summer lands. And I believed entirely in the Ugaro of the winter country and the Lau of the summer country—and in the reasons for their conflict.
Learning about a culture through fish-out-of-water characters. The two main characters are both competent and respected in their own country and confused and inept in the other, and this makes for a humorous and organic way to explore the world.
Military stories. I do not know why I enjoy these: I who have never held a weapon, never taken a martial arts class, believe strongly in peace and diplomacy and think war is a dumb way to solve problems. But it makes for great plots! I loved the two military societies: the tribal Ugaro with their harsh but fair laws governing conflict; the Roman-esque Lau with their orderly hierarchy and comradely soldier culture. I particularly loved watching characters from each society come to appreciate and value those from the other. And I was glad the fighting was not the main focus of the plot, even though there were some great action scenes. I love it when a conversation is more intense than a swordfight.
Heroes with integrity. I love plots that explore what honour is and the conflict of characters determined to do the right thing but not sure what that is. Ryo and Aras are on opposite sides of a war; they are loyal to different countries and believe in different goals; but they are both honourable men who keep their word. I loved watching Ryo negotiate between his duty, his loyalty and his word. I loved how oaths are used in Tuyo: so powerful.
Loyalty and trust. These are themes that stir me deeply, and Neumeier deals with them especially well. One of the main reasons I love the Black Dog books so much is the relationship between Ezekiel and Grayson Lanning—so many punch-in-the-guts moments between them—and the main relationship in this book is possibly even better.
Bromance. See above, re: loyalty and trust. All the feels here. I will not spoil who the bromance is between, but it's the best.
Interesting explorations of women in society. Love it when fantasies try out different ways of imagining women's roles, because, hey, it's fantasy—why wouldn't you?! I enjoyed what Neumeier did with women in the Ugaro society, and the contrast with the Lau and how the characters dealt with it. Female characters didn't play a huge role in this novel, but they were awesome!
Loved the world, loved the characters, am happy to know she intends to write more about them!