1966, Paul Krassner, The Realist, numbers 64-85, page viii:
But at least there is a way to judge soft-core pornography. It gives you a soft-on.
1989, Joani Blank, Good Vibrations: The Complete Guide to Vibrators, page 45:
Later, Al [reported] how amazed he was to have had a second orgasm with a vibrator and a soft-on.
1996, James R. Petersen, 365 Ways to Improve Your Sex Life: From the Files of the Playboy Advisor:
At any point when the tide recedes and the man has a soft-on, he can maintain his partner's level of excitement in the orgasmic continuum by keeping her going.
