Riko and Reg manage to descend deep down into the first layer, the Edge of the Abyss. After eating freshly caught demonfish for breakfast, Riko loses her Star Compass, a relic previously recovered, as it drops down a waterfall. Reg then shows Riko a letter that was slipped into his backpack. It contains a copy of vital information about the Abyss, as well as a note from Jiruo warning them that they will be pursued at dawn...