These are couples from Films, Tv, Books, Comics, and Video Games that I find to be the best in my opinion.
http://www.ranker.com/list/favorite-fictional-couples/christiand-mulkey,
Marshall Eriksen and Lily Aldrin
How I Met Your Mother
Belle and the Beast
Beauty and the Beast
Buffy Summers and Angel
Buffy the Vampire Slayer
Edward Elric and Winry Rockbell
Fullmetal Alchemist
WALL-E and EVE
WALL-E
Hermione Granger and Ronald Weasley
Harry Potter Series
Avatar Aang and Katara
Avatar:The Last Airbender
Clark Kent/Superman and Lois Lane
DC Comics
Percy Jackson and Annabeth Chase
Percy Jackson Series (The Book Series)
Han Solo and Leia Organa
Star Wars