Some time ago the British magazine New Statesman had a humour
competition in which readers were asked to come up with a letter
complaining to the publisher of a sex manual, relating to serious
injury sustained, damage inflicted, or frustration experienced, after
following the instructions contained therein.

Peter Norman won 15 pounds for this:

Dear Sir,

One knows that publishing standards are declining, but I have never
been so shocked and appalled by the number of misprints in a single
publication. I refer, of course, to your 100 Easy Steps to Martial
(sic) Satisfaction. Some of the advice therein is rendered
misleading, dangerous or even illegal by such errors.

For instance, on page 212, one is enjoined to carefully place a
condor on your penis… Later, on the same page, we are told to
stroke the beast, stimulating the erectile tissue at its tip, a
course of action that I fancy even trained falconers would eschew.
Elsewhere, my partner actually followed to the letter (pardon my
little joke) the instructions to fondle your mans bills (p39) and
give him a long, slow message (p128), both of which proved
positively anaphrodisiac. And no one, surely, outside ancient Carthage
has punic hair (p56) or uses a dido (p337). In chapter 1, the
recommended fissionary position (p6) sounds a little explosive for
beginners…