Responses
Yes, Noe and Musutia end up together. Noe outright tells Musutia that he was thinking of him when he would find release with Shin lmao There really wasn't any room for Shin in Noe's heart.
Shin doesn't officially have a partner by the end, but I see a potential sequel for him and his steward Leandros, since I assume he's the important person Shin alludes to in chapter 1.
This is completed on Futekiya: https://futekiya.com/an-unmapped-country-somewhere-in-this-world/
Anyway for those who wants spoilers:
Musutia's disease progresses and he is in dire need of the transplant. However, before that happens, the countries surrounding the island send a messenger requesting Shin back. Turns out he's the third prince of one of the countries (Garche).
Anyway, he negotiates with his brother to help the island and those afflicted with the sickness. Turned out the culprit was inhaling the pollen from a flower that that grew in abundance around them (the graveflowers). So they burn the flowers and Oraie officially opens its borders. Musutia gets a transplant of healthy alveoli from Noe, and they both survive.
There's a 7 year timeskip-- Noe gets a haircut, Shin is a foreign diplomat, and Musutia is in his 20s running Oraie. Noe and Musutia haven't confirmed their feelings or done anything further, so Shin (trying to help the relationship progress) let's out how sensitive Noe's nipples are and basically alludes to their trysts years before. Musutia gets jealous, they confess their feelings, do the deed, and live happily ever after.