What the hairy ball theorem states is that any smooth vector field on a n-sphere must vanish if n is even.[list][*]n = 1: circle[*]n = 2: sphere[*]n = 3: 4 dimensional hyper-sphere[*]⋮[*]n = m: m+1 dimensional hyper-sphere[/list]So for all n that can be expressed n = 2k: ∀kϵℕ a smooth vector field applied over a sphere has to vanish at least one point. This of course also applies to any homeomorphisms of a sphere as well.
However, since pubic hairs aren't infinitesimally thin and the spread of them aren't infinitely dense this does not apply to scrota and pubes.