If you know the wonderful comic novels of Tom Sharpe, in "The Throwback", he has two elderly spinsters mixing egg whites and double cream with a vibrator, to give a lifelike simulation of cum.
The vicars wife turns up unannounced to find the elderly sisters using an icing syringe to fill the balls of a very accurate vibrating balls and penis with the mixture. "What he fuck" says the vicars wife as she sits on the sofa and accidently operates the mechanism of the penis. The thing expands and shakes about with it's veins expanding. The spinsters grab hold of the nine inch mechanical monster in an attempt to stop it. They succeeded all too well. The thing expanded and stopped and shot out half a pint of egg white and whipped cream all over the now screaming vicars wife.
Tom Sharpe writes it so much better than I did. The Throwback - by Tom Sharpe. If you've read it - well done. If not, buy it, read it, and if you don't laugh, you don't have any sense of humour.