Way back, before
Everything, heck, before the
Internet for me
(coincidence or correlation?) when I
was engaging in "sex",
my girlfriend had, in her possession, a single
red lightbulb.
Infra-red burns be damned, whatever room that mighty piece of glasswork was installed in underwent a magical and seamy transformation to a seedy den of wet smells and conspicuous bulges.
I was skeptical myself, but she converted me soon enough.
First person to make the "missionary" joke gets a whack in the kisser.