What is the Ephemeralis? It's part forum and part art exhibition, part gala and part orgy. Mostly it's a theater, but one without scripts or rules or set performances. Wherever the Ephemeralis appears, it is surrounded by a warm glittering mist, sweet as incense-smoke, and a sound like chimes on the air -- and the terrain shifts around within it into an amphitheater bowl, with tiers of pillows on which the spectator-participants recline.
In the center of the amphitheater is the performance ground. Sometimes a poet recites there, or a singer riffs a while; sometimes a band jams; sometimes a dancer leaps and sways; sometimes a talespinner or lorekeeper speaks. There are no rules; spectators are welcome to eat as they watch, or make love, or join in. There is no formal etiquette. If it feels right to stay put and watch a performer, you do that; if it feels right to leap up and join them, you do that.
Some beings follow the Ephemeralis, caught in a continuous, joyous cycle of performing and observing. Most do not, serenely confident that when next they want to attend it, it will be there -- somewhere -- and they will have no trouble finding it.