fish-3
Explanation
The comic depicts a classic fairy tale setup: a fisherman catches a talking fish. In the first panel, the fisherman is excited, exclaiming "My god, I caught a talking fish!" The magical fish offers the traditional deal, telling the fisherman that he may wish for anything in exchange for releasing it, and that the wish will be granted instantly.
The fisherman then wishes for "a magic box that gives me infinite money, except it destroys a random person on Earth each second after I receive any money." The fish grants the wish.
In the final panel, labeled "And so," we see a desert landscape littered with bones and skulls, and the fish (now apparently the sole survivor along with the fisherman) remarks: "This is why magic fish hate loopholes."
The humor works through subversion of the classic "three wishes" fairy tale trope. Normally in these stories, the moral is about greed backfiring -- the wisher asks for too much and suffers consequences. Here, the fisherman has essentially found a way to game the system by constructing an absurdly specific wish that technically grants him infinite wealth, but with a catastrophic side effect he apparently does not care about: the death of one random person per second.
The mathematical horror becomes clear when you do the arithmetic -- at one death per second, the entire human population of Earth (roughly 8 billion people) would be wiped out in about 253 years, though the landscape of bones suggests it has already gone on long enough to cause massive devastation. The fisherman has essentially committed genocide through a loophole wish, treating human lives as an acceptable cost for infinite money.
The fish's final complaint about "loopholes" is funny because it frames the mass extinction not as a moral catastrophe but as an annoying technicality -- the fish is more irritated by the cleverness of the wish than by the apocalyptic result. This is a classic SMBC move: taking a whimsical premise to its darkest logical conclusion.