|Black Lights Don't Like Bottle Blondes|
I don't know the physics and chemistry behind this. However, I know that when black light hits bleached hair, it makes the hair glow.
Oh, and since the bleaching process almost never works evenly across all of the hairs on a woman's head, some hairs glow more than others. This makes a woman's head a mixture of brightly glowing hair, hair that's only glowing a little bit, and hair that doesn't glow at all.
All of that mixed together.
The end result of this is, um, well, unique to say the least. Regardless of how attractive she was - well, with the exception of the hair - it took all of the restraint I could muster to keep a straight face.