Blackmail
Explanation
This is a four-panel comic about a fetish scenario that becomes recursive.
In the first panel, a person in a leather mask tells another person, "You will let me do as I please or I will blackmail you." The other person asks, "How?"
In the third panel, the masked figure explains: "By telling people you participated in this blackmail fantasy!" In the fourth panel, the other person immediately surrenders: "I will do as you bid, sexy Benoit Mandelbrot!"
The caption reads: "Fetish recursion: the ultimate taboo."
The joke is multilayered. The blackmail itself is recursive -- the threat is to reveal that the person participated in the very scenario that contains the threat. This creates a logical loop similar to a Mandelbrot set (a famous fractal named after mathematician Benoit Mandelbrot), which is why the character addresses their partner as "sexy Benoit Mandelbrot." The fractal reference ties the recursive nature of the fetish scenario to the mathematical concept of infinite self-similarity.
The humor comes from applying mathematical concepts (recursion, fractals) to an absurd sexual scenario, which is a very typical SMBC move of finding unexpected connections between intellectual concepts and base human behavior.