Author's Note: Okay, these will vary in length and subject matter. Hope you all enjoy.
Disclaimer: I don't own Naruto.
The casual observer notices something about Sai's artwork immediately.
There is no color.
All of Sai's works are done in black and white. The drawings are not filled in; the paintings are all black strokes on a canvas, touched with gray. No red, no green, no blue; no purple, no yellow, no orange. There is no color here.
They're all colorless. Colorless, stark, and unapproachable. Just like Sai.
Naturally, Sai sees his art in a very different light.
The varying shades of black and gray hit all points of light and shadow, and the faces and forms are fully defined and fleshed-out.
Others see a flower with no color, a lifeless lily.
Sai sees the full spectrum in his work. An entirely different spectrum, but every bit as real.