Two Sides of the Same Coin
Heads is about how reality takes from fantasy. Creative people often take inspiration from art and appropriate it into their own works. Sometimes people get a revelation from art to go out and perform some kind of action, whether positive or negative. An unfortunate example would be crimes inspired by the movie A Clockwork Orange. Art, such as literature, can also uphold or challenge the status quo in the real world. Books like the Bible profess strict gender roles while books like Kate Chopin's The Awakening, which is considered an early feminist novel, argues against the traditional role of women. (Fun fact, I used some pages of the novel in this.) Some folks even try to draw wisdom from astrology, even though there is no evidence that the stars influence anyone.
Music occupies an area between fantasy and reality. A musician writes his idea onto a sheet of special paper. It sits there as symbols, until someone brings along an instrument and plays them - bringing the music to life. (Another fun fact, the music on the right wall and in the shadow are the Song of Healing and Midna's Desperate Hour. They are both from the Legend of Zelda Series and are from Majora's Mask and Twilight Princess, respectively.)