From the Super Mario Wiki
“Princess Peach! Make a wish! A wish for everyone... you, me, Mario... and everybody in the Mushroom Kingdom!”
Twink is a Star Kid in Paper Mario. He is a star that helps Princess Peach in her time of need when she gets kidnapped by Bowser. He frequently gives Mario and his partners information on where the Star Spirits are being held captive. He was born in Starborn Valley. He was then ascended to Star Haven immediately after Bowser stole the Star Rod. If he had ascended any earlier, he would have been trapped there and unable to assist Peach throughout the course of the game. Some dialogue from the other Star Kids still in Starborn Valley suggests that he had somewhat of a big brother relationship with the others and looked after them when he still lived there.
When Peach was first captured, she wished for help, and Twink arrived. Since he was so young, he wasn't able to grant any big wishes. He could, however, assist Peach in eavesdropping around her castle. When Mario and his partners fight Bowser, Twink decides to take on Kammy Koopa. When Twink is fighting, he can only use Dash, while Peach can increase his Attack Power with her wishes (expressed as Focus). Once Kammy is defeated, Mario is given the upgraded version of the Star Beam, the Peach Beam, in which Twink assists the other Star Spirits, making it possible for Mario to defeat Bowser.
At the end of the game, Twink bids farewell to the princess, telling her he's going to make people's wishes come true. It seems that Twink wanted to tell the Princess something further, but he stopped himself and rose up to Star Haven.
Names in other languages