Long ago, when Clefable were being driven off the Moon and cramming into spaceships to take them to earth, one captain defied orders. Believing earthlings were too dangerous for Clefable to rebuild among them, he took his ship away from the Sun and the Earth, aiming for one of Jupiter's moons, but crashed in the asteroid belt and was never heard from again.
His passengers, however, eked out a living on this strange asteroid. They and their descendants began to terraform (or perhaps lunaform) the asteroid, growing mysterious berry plants capable of gaining nutrients from solid rock. However, because the asteroid was made primarily of everstone, once the first generation passed away, this colony became one made up exclusively of Cleffa. Despite their infant forms, they continued to fall in love, have children (unlike Earth's Cleffa, who must evolve before reproduction), wage war, and survive, if on a bleak and barren asteroid far from any other life.
Collisions with other asteroids are frequent, and every now and then, a meteor big enough to contain a Cleffa is dislodged from the main asteroid. Typically, this results in a slow and lonely life, separated from all others they know until they come too close to the Sun and burn up, or drift aimlessly through the asteroid belt for the end of their days. Many of these meteors, however, have found their way to our planet. The Cleffa riding them soon evolve into Clefairy, but they do not join their bretheren in lunar dances and prayer. This is because they do not long for the Moon, but are grateful to live on Earth.
