HUH

They are the same person XD
It's just a resemblance of shin's smart yet awful and stragestic boi that's gonna probably sacrifice shin's love (and health) for his majesty just to make him a great king like he promised :")
It's like you looking at the left and the right Brain talking!~
Hope this makes sense

And if ya look at the last page, the reflection on the water shows nothing. so, it means it's shin's imagination or his inner thoughts.

GOSHHH i really hope one day shin will prioritize himself...