So you're curious about 'butterfly novel'? I'll be honest, I think it really depends on what you mean by 'emotional.' If you're looking for a straightforward, cathartic tearjerker, this might not be the one. It's emotional in a much more subtle, almost claustrophobic way. The prose feels delicate but it's wrapping around something really heavy, like watching a relationship dissolve in slow motion through a fogged window.
A lot of the emotional payoff isn't in big dramatic declarations but in the spaces between sentences, the things the characters refuse to say to each other. I found myself putting the book down sometimes just to sit with a particularly sharp observation about loneliness. That said, the middle section drags a bit with the protagonist's internal monologues, which can feel repetitive. It's not a book I'd recommend for a quick, satisfying cry, but if you enjoy dissecting the quiet fractures in ordinary lives, it leaves a lasting impression. The ending, especially, refuses neat closure in a way that haunted me for days afterwards.