Akiki

Akiki is a tomboyish Ukiki who is the mayor of Jungle Town in Party World. During the events of Mario Party Advance, she, believing her uncle, Ukiki, to have been kidnapped, asks for help from the player and Shroomlock in finding him. If the player succeeds in finding Ukiki, he will return to his house and reveal to the player, Shroomlock, and Akiki that he has simply faked his kidnapping, wanting to play a joke on Akiki. The message Ukiki has left Akiki read, "bIg teAM cAT THElf bLAKE." - the capital letters spell "I am at the lake".

Trivia

 * Akiki's name first appeared on the scorechart for Mario Golf: Toadstool Tour, which was released many years before Mario Party Advance. However, while it's possible that they decided to turn the name on the scorechart into an actual Ukiki character later on, is most likely a coincidence.
 * It could have also been a typo of Ukiki, which is very likely.