"Comic Relief" is a story quest in Hello Kitty Island Adventure that requires you to get the three blue Power Crystals in Rainbow Reef. Due to the location of the Power Crystals, it's unlikely you'll be able to start this quest at the beginning of your playthrough. You should build up your friendship levels with the characters around Island Adventure. This will unlock several tools that are pivotal in reaching the blue Power Crystals, which lie in the depths of Rainbow Reef.