Tamagotchi! anime. The island is shaped as a hollow heart with a rainbow which doubles as the entrance and exit to the island. It is the home of Kizunatchi, Hatokamitchi and Denshohatotchi.
The legendary Ice Tama Heart is found here at the bottom of a small lake, called the Legendary Water (伝説の水 Densetsu no mizu). The island also has its own special fruit, called Heart Berries (ハートベリー).