Where is my Rainbow?

Pechocho has a friend called Spectrum. He enjoys looking at his colors every day. One day, he doesn't see him anymore and gets very sad. This has never happened to him before! He wonders, worries, and dreams about what could have happened to his dear friend. White Cumulus Cloud has swallowed his friend! What can Pechocho do? Does White Cumulus Cloud release his friend? Can Pechocho ever hope to see his friend again?