Vulgar? I'm not so sure about that. I'm pretty sure if you used that as a vulgar insult people would look at you with pity because this is obviously the first time you have been released into the public after being a homeschooled for a decade and you have not quite learned how to use derogatory insults.
Same. What is the intended meaning? Is this an article of clothing, a new language mode after nominative and accusative? A carrying device for anatomical curiosities?
Why is p e n i s considered vulgar anyway? Roughly half of humanity touches one several times a day out of basic needs (urination, folks).
I suppose the intention is that it can be used as a vulgar way to refer to a woman. Although when I have heard phrases like that it's usually something way more vulgar which I won't post publicly. This phrasing is almost humorously innocent in its wording.