Watch and enjoy.
Couples I can recognize are from Sword Art Online, A Certain Scientific Railgun, Chihayafuru, Gravitation, Mirai Nikki, Adventure Time, The Melancholy of Haruhi Suzumiya, Toradora!, Rurouni Kenshin, Full Metal Panic!, Sayonara, Zetsubou-sensei, Fairy Tail, Code Geass, and InuYasha - not necessarily in that order.
