The Eros and Psyche mosaic. In full, in bad light.
From the Enc. Britt.: According to Apuleius, the jealous Venus commanded her son Cupid (the god of love) to inspire Psyche with love for the most despicable of men. Instead, Cupid placed Psyche in a remote palace where he could visit her secretly and, by his warning, only in total darkness. One night Psyche lit a lamp and found that the figure at her side was the god of love himself. When a drop of oil from the lamp awakened him, he reproached Psyche and fled. Wandering the earth in search of him, Psyche fell into the hands of Venus, who imposed upon her difficult tasks. Finally, touched by Psyche's repentance, Cupid rescued her, and, at his instigation, Jupiter made her immortal and gave her in marriage to Cupid.