Impa

"I am Impa of the Sheikah. I am responsible for protecting Princess Zelda."

- Impa: Legend of Zelda Ocarina of Time

Impa of the Sheikah is guardian of Princess Zelda in the game Legend of Zelda Ocarina of Time. As the last of the Sheikah, Impa is sworn to protect the royal family at the cost of her own life if necessary and has both the knowledge and skills to make her one of Hyrule's best possible bodyguards.

The Sheikah
The Sheikah are an ancient people native to the village of Kakariko, at the base of the treacherous Death Mountain. The Sheikah have a history of using black-magic and both summoning and combating evil spirits. The graveyard of Kakariko Village houses numerous graves reserved specifically for the Sheikah. Kakariko Graveyard's tombstones not only act as monuments to honor the dead but also serve to seal the souls of the Sheikah who remain restlessly vigilant even after death. Impa was the leader of Kakariko Village prior to being recruited by the royal family to guard Princess Zelda as her personal bodyguard.

Zelda's Bodyguard
Link will encounter Impa inside the Hyruyle Royal Palace immediately after speaking with Princess Zelda and accepting her mission to stop Ganondorf from gaining the Trifroce of Power. Impa will teach Link Zelda's Lullaby. As Impa played the Sheikah's ancestral melody to the Royal Family as a lullaby, the song doubles as a sign of trust between the player and the royal family, thus playing the song hence-forth will serve to prove Link is an agent of the Royal family like Impa. After teaching Link the song Impa will escort Link outside the palace and point out Death Mountain, outlying his path to the home of the Gorons to gain their help in his quest.

After gaining the Sacred Ruby from the Gorons and the Sapphire from the aquatic Zoras, Link will return to Hyrule Castle to unite them with Princess Zelda, thus sealing the Triforce. However upon his arrival outside Hyrule Castle Link will witness Impa speeding away from the castle on horseback, with Zelda in her arms and Ganondorf shortly behind. Zelda will throw her Ocarina, the titular Ocarina of Time, into the moat upon seeing Link, in attempt to get it in safe hands. After being tossed aside by Ganondorf in his chase, Link will retrieve the ocarina from the moat and use it and the sacred stones to enter the Temple of Time and secure the Triforce himself. Once Link enters the Temple's sealed room Ganondorf will make his move, seizing the Triforce will leave Link caught in the Sacred Realm. The sage, Rauru will keep Link in stasis until he is old enough to wield the realm's sacred Master Sword and stop Ganondorf. In seven years Link awakens to save the land from the evil Ganondorf has unleashed.

The Shadow Temple
In his quest to get the help of the seven sages of the Sacred Realm Link must go to each of their temples across Hyrule and free them from the evils Ganondorff has placed inside them to corrupt and oppress their regions. The Shadow Temple is revealed to be in Kakariko Village, just above the graveyard. Link must fight the evil Bongo Bongo, the ghost of a murderous sage who lived in Kakariko long ago and who took up residence in the Shadow Temple once Ganondorf broke his seal. Traveling through the twisting dark and haunted passages of the Shadow Temple will eventually place Link in the lowest chamber, facing the evil spirit. Defeating Bongo Bongo will allow the spirit of the temple's sage to reclaim it and aid Link in his quest, as it turns out, Impa is the newest Sage of Shadow. Impa praises, Link not only for freeing her ancestral temple, but for embarking on his quest to honor Princess Zelda. Impa tells Link he shall meet Zelda again before the end, then gives Link her power in the form of the Medallion of Shadow. Like all the other sages, Impa will add her power to Link's in Ganondorf's castle to overcome his evil seals. Upon beating Ganondorf and finishing the game Impa and her fellow sages will be seen meeting on top of Death Mountain rejoicing at the freed land of Hyrule. It is implied that all the Sages are spirits and thus had been killed and recruited by the temples as the new keepers there of, but it is never stated outright that Impa or any of the other sages are actually dead, but they clearly can no longer walk the land of the living.