sadism
Explanation
The Joke
A dominatrix tells her submissive client: "I'm gonna put you in this goggle. You will sit here, in darkness, thinking dirty thoughts, until I come back for you." The submissive obediently replies "Oh yes, mistress." The next panels reveal what the "dirty thoughts" goggles actually show: a to-do list that reads "Mine every slice of mine" or similar mundane/torturous content. The final panel shows the dominatrix enjoying a slice of pizza while the submissive suffers.
The comic subverts expectations about BDSM by presenting a dominatrix whose method of "torture" is not physical pain or sexual teasing, but something far more psychologically cruel -- forcing someone to confront mundane, anxiety-inducing tasks or be bored while she enjoys herself. The goggles, which the submissive expects will deliver some kind of intense sensory experience, instead deliver tedium or domestic obligations.
The Humor
The humor comes from the gap between what the submissive expects (sexual punishment) and what he gets (something genuinely, mundanely unpleasant). True sadism, the comic suggests, is not whips and chains -- it is making someone sit alone with boring or stressful thoughts while you eat pizza. The comic also plays with the idea that real psychological torment is far more ordinary than the theatrical version. The dominatrix's true cruelty is not in the dungeon trappings but in her casual enjoyment of life while her client suffers through banality.