It is an odd response. What a cringy stab, rather failed attempt at being clever. It's distracting from the topic at hand and excruciatingly awkward.

However, it seems the commenter was trying for sarcastic humor. It looks like she's commenting on the standard medical illustration of male genitalia in textbooks – which were illustrated that way to not be titillating.

The Groucho emoji is pretty standard to indicate cringy humor – he was the master of truly funny cringe.