With the help of big glass, it's easy to visualize the texture of butterfly's wing. I then realized that butterfly, like human being, have gone through frictions during mating. Butterflies may come out from a cocoon young and free. They then have to join the mating population, which is the ruthless arena of reproduction. After a successful "marriage", they seem exhausted and will hide in a shadowed place with their wings showing "the unbearable heaviness of being".