compatible
Explanation
The Joke
A couple is in what appears to be a therapy or relationship counseling session. The therapist says, "Let us talk about your sexual compatibility issues." One partner (a woman) says, "I wish he would initiate more." The man responds with his own complaint: "And you, Sally?" She then launches into an elaborate scientific tangent about having "created a coding-theory-based method to optimize signals that remain perfectly still while broadcasting male and female gametes into the environment." The therapist responds, "It is literally impossible -- call it inappropriate." In the final panel, the man whispers to his partner, "I meant for my ex-girlfriend," and the woman says, "She always does this."
The Humor
The comic operates on multiple levels of miscommunication. The initial setup is a standard couples therapy scene about sexual compatibility, but it quickly derails when one partner interprets "sexual compatibility" through the lens of evolutionary biology rather than relationship dynamics. Her proposed solution -- broadcasting gametes into the environment like a sessile marine organism (such as coral or sea sponges) -- is a method of reproduction used by some animals and plants but is hilariously incompatible with human relationships.
The joke satirizes a certain type of hyper-analytical person who responds to emotional or interpersonal problems with technical solutions from an entirely wrong domain. Instead of addressing the actual relationship issue ("I wish he would initiate more"), she has been working on optimizing a broadcast-spawning reproductive strategy, which is the biological opposite of "initiating" in a relationship context.
The final panel adds a secondary punchline: the whispering suggests this is not even the right couple being counseled, or that the man was talking about someone else entirely, compounding the layers of miscommunication. The therapist declaring the idea "literally impossible" and "inappropriate" captures the exasperation of trying to counsel someone who has redefined the problem into a different scientific discipline entirely.