The island and it´s surroundings are covered in star fruit and their trees. This is also place where player meet Nekoyama.
Role in Wadanohara and the Great Blue Sea
After coming back from the Witch World, Wadanohara and her familiars discovers a trail of letters coming from Star Isle.
In Wadanohara's flashback, Wadanohara and Samekichi are seen interacting at the Star Isle. This is the place where Samekichi gifted Wadanohara an ocarina during night, and also confessed his feelings to Wadanohara.