The story of Cupid and Psyche is often considered to be one of the first "fairy tales" ever recorded in writing, included as it was by the Roman author Apuleius in his novel, The Golden Ass. It's a long and delightful story; I won't try to summarize it here, but you can read a nice summary of the plot at Wikipedia. The painting is by John Roddam Spencer-Stanhope and shows the moment when Cupid has been ordered by his mother Venus to make the beautiful Psyche fall in love with some scandalously ugly creature. As things turn out, of course, Cupid will fall in love with her himself!
You can also find more myths and legends for the week of March 25-31 here. For more information and links to the actual javascript code, see the Myths & Legends Widget Reference Page.