The art quality here is very good, but half of the things look flipped left/right. You can tell because Kawori is holding the instrument backwards, and the lid on the grand piano is backwards as well. It looks like the text on the piano is backwards also, although it's barely legible. The score on the sheet music looks like it is in the correct direction.
Tip for artists drawing violinists: The left hand holds the instrument, and the right hand holds the bow. (The show consistently portrays this accurately.) I played the violin from 5th grade through college (and sporadically thereafter), and I've never seen a violin that was built to be played the other way around, although a mirror-image one could be custom built I suppose. The instrument itself is asymmetric in many of its components, and you would have to do the finger work backwards if you held a normal violin opposite-handed.
For pianos, when opened the lid on a grand piano is intended to reflect the sounds from the strings towards the audience. So in performance, a grand piano is typically set up so the audience is on the player's right side.