It's just magnets most likely:) Same goes with removable/adjustable head hair. You have a lot of good, strong magnets all around the area against the foam of the head, and shave the fur down along those magnets pretty close to the backing. The removable part, like eyebrows or head hair, have the other side of the magnet exposed usually on the back of the adjustable piece. So one side of the magnet is under the shaved fur, the other side is exposed on the back of the piece.
As for glow in the dark or black light, I'd ask round. Most fursuit makers find their fur to match what you want, and that kind of fur isn't impossible to find, specifically a neon color. Most who have a glow in the dark effect actually have led lights in the suit, for stripes or spots for raves and whatnot
Hope that all made sense