The Realm of Light
Crafted by the Entities as a metaphysical plane, it exists above Ayn and out of the material world, which is to say it is unseen by the naked eye. Many consider it to be an eternal afterlife and a place of never ending joy and cheer, and while that is somewhat true, the afterlife is not eternal. Short of a few places specific, such as the places only angels can go, it is mostly open for the array of souls and spirits that visit. Here, they are eased to rest, assisted as they meet with friends and family they need to say goodbye to, or helping them achieve their life's work to satisfaction. When the soul is at ease and ready to pass on, it will dissipate back into essence which can then be used for new life or a multitude of other uses.
Although the terrain can shift to suit the needs of the departed (Such as forming a large mountain for one final adventurous trek), its default state is vast rolling waves of clouds that are just heavy and dense enough to allow a spirit to walk freely. It is said the sun pours a gentle glow over the puffs, creating a shimmering, golden effect.
Fauna & Flora
In its default, no actual flora or fauna grow here. However, it is worth noting that animals, generally, do come to the Realm of Light when they pass. Their stay is usually very short lived considering their needs are incredibly simple. A pet, however, may wait for its owner for a final ear scratch, or one last playtime before passing on.
"And lo as Joeb ascended to the Kingdom of Light, his soul was at peace. His body was surrounded by those that he loved, cherished, and stood beside...But soon his spirit would be surrounded by his ancestors, ready to greet him, eager to hear his many stories he used to delight his grandchildren." -The Gifts We Give, Chapter 12