Namine

Namine is a girl from Castle Oblivion in Kingdom Hearts: Chain of Memories. She met Sora, Donald, and Goofy for the first time after they defeated Larxene in a battle.

In the end, Namine and Sora used their pinkies for a promise, known as a Pinkie Promise so she says goodbye to Sora, Donald, and Goofy, and disappeared.