Couples

Couples by John Updike
Oscar and Lucinda
Arthur and George
Oryx and Crake
The Professor and the Madman

archy and mehitabel by Don Marquis
Dave Barry's Guide to Marriage And/or Sex
The Letters of Abelard and Heloise
Caesar and Cleopatra by George Bernard Shaw
Eleanor of Aquitaine and the Four Kings by Amy Kelly

Death and the Devil: A Novel, by Frank Schatzing
Lily and Hodge and Dr.Johnson, by Samuel Johnson (oh, okay, so it's a threesome, so sue me.)
Magdalena and Balthasar : an intimate portrait of life in 16th-century Europe, by Steven Ozment
Aunt Julia and the Scriptwriter, by Mario Vargas Llosa
Two visionary brothers : David and Alfred Smart, by David Mazie

The Diaries of Adam and Eve by Mark Twain
Sheldon and Mrs. Levine, an Excruciating Correspondence by Sam Bobrick
Romeo and Juliet by William Shakespeare
Sir Gawain and the Green Knight
The Master and Margarita by Mikhail Bulgakov

Nelson and Emma edited by Roger Hudson
Tim and Pete by James Robert Baker
Martin and John by Dale Peck (I liked the original title better, but I won't repeat it here...)
Sammy and Rosie get laid (filmscript) by Hanif Kureishi
Oscar and Lucinda by Peter Carey

Anna and the King of Siam by Margaret Landon
I & Claudius: travels with my cat by Clare de Vries
Franklin & Eleanor by Cheryl Harness
Big Russ and Me by Tim Russert
Elizabeth and Mary by Jane Dunn

The Marriage of Cadmus and Harmony by Roberto Calasso
Clea and Zeus Divorce by Emily Prager
Bunny Brown and his Sister Sue by Laura Lee Hope
The Egg and I by Betty MacDonald
The Two Towers by J.R.R. Tolkein

Jonathan Strange and Mr. Norrell by Susanna Clarke
Angels and Demons by Dan Brown
Mr. Bridge and Mrs. Bridge by Evan S. Connell
Two Little Girls in Blue by Mary Higgins Clark
Love Sick: A Smoldering Look at Love, Lust, and Marriage by Michael J. Nelson

The Chymical Wedding
Herb 'n' Lorna
Simple Living: One Couple's Search for a Better Life
Unmarried to Each other: The Essential Guide to Living together as an unmarried couple
Saving Your Marriage Before it Starts

Mara and Dann
Margaret and I a novel
Foundation and Earth
Orion and the Conqueror
The two of them

The Prince and the Showgirl by Laurence Olivier
Adam and Eve and pinch me by Ruth Rendell
Elvis and the Colonel by Dirk Vellenga
Emma and I by Sheila Hocken
Angels and Aliens by Keith Thompson

What Janet and John Did Next by Mick Sturbs
The Prince and the Lily by James Brough
Ethel and Ernest by Raymond Briggs
The Brothers Karamazov by Fyodor Dostoevsky
Dombey and Son by Charles Dickens

Hedwig and Berti by Frieda Arkin
Jack and Rochelle by Jack Sutin
Ava's Man by Rick Bragg
The Kitchen God's Wife by Amy Tan
Two Women by Alberto Moravia

Blood and Gold by Anne Rice
Foundation and Empire by Isaac Asimov
Romeo and Juliet by William Shakespeare
The Strange Case of Dr. Jekyll and Mr. Hyde by Robert Louis Stevenson
My Sister's Keeper by Jodi Picoult

Juno and Juliet Julian Gough
Peter and Mary Have a Row Damien Owens
Things My Girlfriend and I Have Argued About Mil Millington
Shopaholic and Sister Sophie Kinsella
Man and Wife Tony Parsons

Holmes and Watson by June Thompson
Single and Single by John LeCarre
The Letters of John and Abigail Adams by Abigail Adams
The Prince and the Pauper by Mark Twain
Peter and the Wolf by Sergei Prokofiev

Jack and Jill by James Patterson
Kane and Abel by Jeffrey Archer
Antony and Cleopatra by William Shakespeare
You and Me, Babe by Chuck Barris
Morgan and Me by Stephen Cosgrove

Darcy and Elizabeth by Linda Berdoll
The Lady and the Unicorn by Tracy Chevalier
Troilus and Cressida by William Shakespeare
The Amazing Adventures of Kavalier and Clay by Michael Chabon
Franny and Zooey by J.D. Salinger

Anita and me by Meera Syal
Frankie and Stankie by Barbara Trapido
Benny & Shrimp by Katarina Mazetti
Calvin and Hobbes by Bill Watterson
Cat and Mouse by James Patterson

Edited to replace Arther and George with Frankie and Stankie.