Sushie is a purple Cheep-Cheep who babysits the Baby Yoshies on Lavalava Island in Paper Mario for the Nintendo 64. Sushie is very attentive to the Baby Yoshis' schemes, and so she often ruins them. Sushie also has a daughter named Sashimie, who is going to have a baby, making Sushie a grandmother. Sushie helps Mario by ferrying him across bodies of water, but only if they are on a wooden platform. In battle, she specializes in water attacks, making her useful against fire enemies. Her name, as well as her daughter Sashimie, are spoofs of various Japanese fish served raw, sushi and sashimi respectively.
“Uh-huh... Oh... Oh! You're going to the volcano because you want to save the princess from some bad guys? What...a touching story! Romantic stories like that... just touch a soft spot in this heart of mine. That does it! I can't let you go alone! I, Sushie, will be by your side until the end!” —Sushie, Paper Mario
Sushie is Mario's seventh party member in Paper Mario. In Super Paper Mario, Sushie appears as a Catch Card found on the eightieth floor of the Flopside Pit of 100 Trials, as well as on a photo in Mario's house.
Her pause menu description states that she "loves romantic stories and cries at the drop of a fin", implying that she is very sensitive and soft-hearted.
According to the Yoshi children, she is very bossy.
At Lavalava Island, Mario enters Yoshi Village and finds that five Yoshi children are missing. Their babysitter, a Cheep-Cheep named Sushie, asks Mario to help her find them. When they find the 5 Yoshis, Mario tells Sushie about his quest. Sushie says it's a very romantic story and joins the party.
By pressing C-Down, after Mario reaches a dock, Mario can swim on the surface of water and dive if he presses C-Down again.
Sushie has a daughter named Sashimie. During the game, Sashimie sends her mother a letter, stating that she is going to have a baby, meaning Sushie will soon be a grandmother.
Like the other Paper Mario partners, Sushie was originally going to appear with updated sprites in the sequel, Paper Mario: The Thousand-Year Door, however she and most of the others were removed for unknown reasons.
Sushie is the only partner in Paper Mario that didn't have any prior knowledge of Mario (as she, herself, states that she's never heard of him).
Sushie is referred to as "he" and "him" on the Super Rank description.