Fifteen Cent is a parody of Curtis "50 Cent" Jackson & Lil Bow Wow. As his appearance is a young braid wearing rapper.
Fifteen was looking for "Spare Change" backup dancers for a halftime show at the Wizard Kelly Stadium. Penny Proud and her friends try to audition, but the dance intruder said they're not in. But Fifteen had an affection for Penny, and said her and her friends are in. He then asks Penny if he can drive her home.
When they arrived the Penny's house, she assumes he wants a kiss on the first date. But she told him to forget about it, explaining Fifteen about his exploits in Dreamy Teen Magazine about his multiple relationships, especially with Christina Aguilera. But Fifteen insures her the stuff in those magazines are all made up, and that he didn't want to upset his mother if he misses his curfew. He implied that it's getting late and he had to return his grandmother's truck. Realizing he doesn't want to mess with Penny and figuring she might not get the chance, she grabs Fifteen's face and start kissing him. But then Oscar Proud, Penny's overprotective father, gets mad when he finds them kissing.
After Penny returned from her vacation with the clones of her family made by the evil Dr. Carver clone, thinking they were her real family, the Oscar clone said it was okay to her to go and being one of Fifteen's backup dancers. He picked up Penny to bring her to rehearsal. While they were practicing, the Oscar clone arrived to take the formula in Penny's locket. He was ineffably caught, and everyone thought he was just there to dance. Penny was embarrassed, though Fifteen thought he was alright.
After Penny saved the stadium from the Carver clone, it was covered in peanut butter. Not to disappoint his fans, Fifteen told them it was all part of his new song. He then let Penny and her friends take over the halftime show. After telling his cousin Sticky Webb he throwing a party at his yacht, Sticky tries explaining to him that they've crashed it. He then got into the group photo with everyone else.
Fifteen loves to call Penny "Ponytail".