Kiki
Kiki is a little blue monkey in A Link to the Past. He appears when Link is wandering through the maze of brush on his way to the first Dark World dungeon. Kiki loves rupees more than anything in the world, and for a small fee he follows Link through the rest of the journey to the dungeon. Upon arriving, Kiki informs Link that he knows how to open up the sealed entrance, and for a substantial fee Kiki opens the door to Palace of Darkness.
Kiki also makes another brief appearance in Link's Awakening, where he and his other monkey friends build a bridge when he receives bananas during the Link's Awakening trading sequence.