Who is Arabella Allen from The Posthumous Papers of the Pickwick Club and what is their importance?

Arabella Allen is one of Isabella's friends. While attending Isabella's wedding, Arabella meets Nathaniel Winkle, and the two begin a romance. When Winkle visits Arabella in Bristol, the couple confesses their mutual love. Much to the chagrin of their families, the couple elopes. After their elopement, they ask Mr. Pickwick to talk to their families to reconcile them to the match. Although Mr. Winkle, Sr. disapproves of the match at first, he changes his mind after meeting Arabella. Arabella and Winkle live in London where Winkle obtains a good job through his father's help.