Who is William Pickering from The Virgin's Lover and what is their importance?

William Pickering, a wealthy and handsome young Englishman, is one of Elizabeth's childhood friends from the time when she was a young girl and not in direct danger from Queen Mary Tudor. It is rumored that there was an affair or a romance during their youth, and when he arrives back on the scene William Pickering captures her heart once more. Elizabeth ignores all other men and suitors for her hand and instead spends all of her time with William Pickering, until it becomes obvious that she must choose a husband to defend her realm. During this emotional confusion Robert Dudley makes his move and William Pickering leaves the court, apparently upset and angry. It is learned from the lords of the Privy Council that William Pickering had been encouraged to stay by them as an alternate candidate to Robert Dudley, because they despise Dudley.