The Red Orchid Norns were created by Lisa and Neogecko and can be downloaded at The Mystical Forests of Albia. They use a special genome designed by Neogecko. They are able to feed on warmth and humidity, just like plants do. However, there's also a standard CL genome version to prevent the death of offspring when cross-breeding other norns with the special Red Orchid genome.
Note that the download link for the female sprites is incorrectly linked. You need to type in manually the same download link in your browser as for the male sprites and add "/Red_Orchid(female).exe" at the end instead.