Compact Mirror
From Starfy Wiki
The Compact Mirror (Japanese: コンパクト) is an item in Densetsu no Starfy 3, found in Coral Coast (Stage 2-1, map 3). It is Ruby's favorite compact mirror. Ruby left this item behind while moving from a pink roofed house to a larger red roofed house. Other items that were left behind are the Perfume, the Hand Mirror and the Necklace. The Compact Mirror and the other items all got stuck in bark. Starfy must ring one Coral Bell to reveal the Hand Mirror.
When Starfy and Starly give Ruby the four items, she is grateful and rewards them with the Necklace Accessory.