Now I show that for the upper-left red point, it has 3 GG neighbors that are red, and the blue point is not a GG neighbor, so the upper-left red point will also be discarded. By symmetry the same applies for the lower-right red point. Trivially, we can see that no other points are discarded.

So our set X

We see that the blue point is the closest, so the red point will be classified as blue, incorrectly.