Sometimes, you have to consider where elastic will land.
You can't just leave it to chance. You have to look at your design and think where it's likely to fall nine times out of ten. If that place will inadvertently trigger a childish joke, you must think again; how much does anyone need their books held closed anyway?
I spotted the offending article in the window of a second-hand bookshop, which was only to be expected; I wouldn't want such filth to remain in my house either; no sooner would I have spotted it than it would be out, on the street if necessary. I don't want it to be misconstrued; an impromptu visitor might see it as a come-on.
Also, why does the sign next to the book need to set the caveat of selling complete jigsaws anyway? Isn't that obvious? And the promise of a ceiling price of £1 is an empty boast, particularly when the current coin will soon no longer be legal tender. This window display is a bloody joke.