OH, LUKA, EVERY WOMAN WHO WORKS IN THE HOSPITAL KNOWS WHO YOU ARE. TRUST ME: Benton and Carla. Benton and Jeanie. Benton and Corday. Benton and the Cleo-Bot. John Truman Carter with Harper Tracy, Anna Del Amico, Abby Keaton, Susan Lewis, Rena (the teenager), Lucy Knight, the cancer patient played by Rebecca de Mornay, Liz (the one with a doctor fixation and gonorrhea), Abby Lockhart, Roxanne (the volleyball-playing insurance saleswoman played by Julie Bowen), Wendall and Kem. Carol Hathaway and Tag, Shep, Luka (briefly) and, of course, Doug Ross, the one relationship we'd probably all pick as the core romantic (as opposed to bromantic) relationship in the fifteen-year history of ER.
That's not to say we can't have other favorites too, and I want to note two favorite flings -- Carter and Keaton's clandestine surgeon-student thing that had them both giggling, and Mark's midlife crisis post-divorce hookup with nurse Chuny, because it made no sense whatsoever. Yours?