Richard Lewis is a comedian and friend of Larry David.
Richard and Larry apparantly knew each other for a long time and have a number of things in common, both being comedians and moving from Los Angeles to New York to pursue their careers. Richard is also a recovering alcoholic and drug abuser, which is occasionally used as a running gag. Throughout the series Richard dates a number of girls more attractive than him and who he always claims is "the one." The relationships are usually ruined by Larry's antics or Richard breaks up with the girl for superficial reasons. In season five Richard Lewis developed Kidney Disease and needed a transplant. When it turned out both Larry and Jeff Greene were blood type matches, the two fought over who would be forced to give the kidney. Larry decided he would do it in the season finale after a life changing trip to Arizona, though he quickly tried to get out of it after he reverted to his old ways. Richard got the kidney from Larry and went on vacation with a new girlfriend, even though Larry was dying from the post-transplant.