Chaucer really zooms in on just three people for this one. The Miller himself, who's telling the tale, is a loud, drunk, and bawdy character even before the story starts. His tale revolves around a love triangle. There's Nicholas, the crafty scholar who's renting a room from the carpenter. He's clever but entirely self-serving, faking an apocalyptic vision to get what he wants. Then you've got the carpenter John, who's older, jealous, and pretty gullible—he falls for Nicholas's scheme completely. And Alison, John's young wife, who's described with all this earthy, animalistic imagery. She's not just a passive object though; she actively chooses Nicholas and participates in the trick. Absolon, the foppish parish clerk who also pursues Alison, provides the comedic humiliation with his misplaced romantic gestures. It's a tight cast of flawed, lusty people designed for a specific kind of raucous joke.
What's interesting is how the Miller uses them to directly mock the Knight's noble, idealized romance that came before. These aren't heroes; they're lusty, deceitful, and vain. The key dynamic is the contest between cleverness (Nicholas) and foolishness (John and Absolon), with Alison as the prize they're all scrambling for. The tale ends with everyone getting a sort of crude, physical comeuppance, which feels perfectly in character for the Miller telling it.