Mr. Wickham is a handsome, charming man who is only interested in upgrading his status and class in society. Mrs. Gardiner, who is much like a surrogate parent to Elizabeth, recognizes this in Mr. Wickham and tells her that he would be an unsuitable match for Elizabeth. Darcy also warns Elizabeth about Mr. Wickham when he tells her Wickham tried to elope with Darcy's sister to get his hands on her money.
Mr. Wickham is an example of the pride and class themes in the book. Wickham's desire to marry for money offends Elizabeth's sense of pride and shows Wickham is willing to put money and class before his own pride. It's ironic that Charlotte Lucas does the same thing as Wickham. Charlotte decides to marry for money rather than love when she agrees to marry William Collins. Both Charlotte and Wickham equate money with the upper class and want to improve their status in society.