* Mr. Brocklehurst: The harsh and unforgiving headmaster of Lowood Institution is a caricature of religious hypocrisy. His character is driven by a single, exaggerated trait: cruelty. He serves primarily to illustrate the oppressive nature of the Victorian social system and to contrast with Jane's eventual independence.
* John Reed: Jane's cruel cousin is a one-dimensional representation of brute force and entitlement. He exists to demonstrate the unfair treatment Jane endures in her early life and to set up the theme of social injustice.
* Blanche Ingram: This flamboyant and narcissistic socialite is primarily defined by her superficiality and vanity. She serves as a foil to Jane, highlighting Jane's inner beauty and genuine character.
* Mrs. Reed: Jane's aunt, although a complex character, can be viewed as somewhat flat in her role as the embodiment of social snobbery and a source of Jane's childhood suffering.
* Richard Mason: This character, although briefly introduced, is primarily a plot device to propel the action forward. He lacks depth and serves mainly as a victim in the narrative.
It's important to remember that the term "flat character" isn't necessarily a negative judgment. These characters are essential to the story, serving specific functions within the narrative, even if they lack complexity.
However, it's worth noting that some readers might find these characters more complex than others. For example, while Mr. Brocklehurst might seem like a caricature of cruelty, his motivations and the influence of his social environment could be explored further.
Ultimately, the level of complexity assigned to these characters is a matter of interpretation.