Fi

Skyward Sword

Link's sidekick in this game appears as a female spirit-like entity named Fi. She is the very embodiment of the Goddess Sword itself, which allows Link to travel freely between the sky realm and the surface world below. Her origins are a mystery, as she appears from the sky above Link after he's thrown off his bird by Ghirahim's tornado and saves Link from the fall. Later, Link brandishes the Goddess Sword and with her advising and aiding him he journeys to the Forest Temple where he finds an evil sorcerer, Demon Lord Ghirahim. The Lord himself states that the Goddess Sword is the only thing that kept Link alive during their fight.

Fi's humanoid form appears by expanding out of a light from the hilt of the Goddess Sword and disappears by shrinking and returning to that light. She doesn't seem to act human, speaking to Link with a cold, robotic monologue as she analyzes his items and surroundings and gives him information about them. When Link enters a new area, Fi comes out of the sword and announces where you are and a very brief blip about it. Also, when Link finds an upgrade or a new item, Fi comes out of the sword and tells you what the item is and what it does. When she talks to Link, she refers to him as master. Why she acts this way is also, like her origin, a mystery.

The Goddess Sword is somehow important to the forging of the Master Sword, exactly how has yet to be revealed.