In the quote from Thomas Pynchon's "Mason & Dixon," the author reflects on the character Shelby, likening him to a middle-aged Imp. This suggests a blend of mischief and malevolence that persists through time, hinting at an enduring, perhaps even enjoyable, malice that characterizes him.

The description of Shelby emphasizes his busy life, suggesting that despite his wicked nature, he is often preoccupied with daily tasks. This juxtaposition of malevolence and routine life highlights the complex nature of his character, evoking curiosity about how his 'Imp-like' characteristics might manifest as he navigates through his commitments.