I won't give a review right now, because I don't want to give a bad one, and looks like the Dev is reading this post which is nice.
The game doesn't stand by itself until Myla's first appearance, she seems like a nice sweet and naive girl, and a liked every scene she's in.
But before that, It seems like you created Shiro to explain to us what everything is about, he's your exposition dump guy, and for every new concept that you think that we won't understand, I know he's gonna be there.
Without him breaking the pacing would be a very good Visual Novel, because looks like Sandbox is tied to the story either way.