Almost everyone can understand irrational fear. Phobias exist almost everywhere, and by dictionary definition, its disproportional fear to the actual dangers. In clinical psychology, its defined as a type of anxiety disorder. It belongs in the same category as people who are afraid of small rodents, small spaces, large spaces and meteors. Almost anyone with a phobia can put themselves in the shoes of someone else with a different phobia.

It should be added that around 10% of adults has some kind of phobia. Its common, and perfect understandable. At the same time, there is not much anyone can do about it. Avoiding all possible triggers for phobias is neither a option nor is it even a good thing. Treatments for phobias often include some kind of desensitisation by exposure, so avoidance is actually decremental.

That said, crude jokes are boring. I would just had told the two guys to be quiet because the python talk is infinitive more interesting than some crude joke regarding anatomy.