coupling
Explanation
The Joke
Two aliens are observing a human couple as part of what appears to be a xenobiology or xenosociology experiment. They explain to a visitor that they take a human couple, alter their chemical profile, and watch as the couple -- who previously found each other physically attractive and sexually desirable -- can no longer explain their attraction. The humans then conclude they are "no longer in love."
The comic then shows the human couple going through a relationship crisis. The man says he was so invested in the relationship that he forgot to maintain his own identity. The woman panics, asking what his statements mean. Later, they reflect that they confused infatuation with genuine love. In each case, the aliens react with howling laughter, treating the humans' emotional turmoil as the funniest comedy show in the galaxy. The final panel reveals the humans looking uncomfortable while the aliens declare it a "forced coupling experiment" and the funniest show around.
The Humor
The joke operates by reframing human romantic relationships from an alien perspective. All the deeply felt emotional experiences of falling in and out of love -- the existential crises, the anxious self-examination, the tortured breakup conversations -- are revealed to be, from an outside perspective, merely the predictable biochemical responses of organisms whose hormones have been tweaked. The aliens find it hilarious that humans construct elaborate emotional narratives around what is essentially chemistry. It is a sharp commentary on the gap between how meaningful romantic suffering feels from the inside and how mechanistic it looks from the outside.
References
The comic touches on the scientific understanding that romantic attraction is heavily mediated by neurochemicals such as dopamine, oxytocin, and serotonin. The "chemical profile" the aliens manipulate likely refers to these systems. Research has shown that the intense feeling of "being in love" correlates with specific hormonal states that naturally diminish over time, which the comic exaggerates into a deliberate experimental manipulation.