She looks more natural this way, all the ribcage and collarbone are aligning perfectly with her small breast's and for some reason it is relateable to her daily life as musicians rockstar lifestyle.
If so, he internalized it long ago, because it's the established style Yuzawa has had since he's been posting things roughly a decade ago (compare other works of his). I'd be more inclined to think he simply has a thing for thick body hair, overly pointy nipples, and prominently bony bodies.