Written in around the 2nd century AD by Apuleius within his Metamorphoses, better known as The Golden Ass to many, Cupid and Psyche had originally appeared in art since 4th century BC. The tale tells of two lovers that only come together because of Cupid's mother, Venus, deciding that Psyche was far too beautiful and, therefore, had to be punished. Cupid accidentally pricks himself instead, falling deep in love with Psyche, who is told by an oracle she must give herself up to a "monster" as part of her destiny. This story is considered one of the greater love stories of Ancient Greece, and is still heavily referenced in modern day popular culture, especially as it is the insperation for tales such as Beauty and the Beast. 

The added picture is Psyche et L'Amour by Bouguereau.