Who is James Harlowe from Clarissa and what is their importance?

James Harlowe is Clarissa's brother. He is very jealous of Clarissa because she inherited their grandfather's estate. James initiates the scheme against Clarissa, which in turn, results in her elopement with Mr. Lovelace and her eventual ruin. James is described as very greedy, proud and violent. After Clarissa's death, he plans revenge against Mr. Lovelace. James believes that the unhappiness in his marriage is punishment for his maltreatment of Clarissa.