That isn't cell shaded. Cell shading looks like this.

No matter where I look at the box, there will always be that outline.
You spelled "cel shaded" wrong, and that example you posted isn't cel shaded. It's merely flat shaded with an outline.
I have no goddamn idea why, but everyone thinks cel shaded means outlined, even though the word "SHADED" is in there. The outline is optional, while the actual shading isn't.

THAT is cel shaded. Notice the hard shadows and bright cartoon-like colors? That's what makes it cel shaded. There's no outline, either.