When Cleveland Brown tries to set his son Cleveland Brown Jr. up with Flora, a server at Chonie's Cantina in "Y Tu Junior Tambien", he instead makes a connection with Cecilia, Choni's smoking hot niece. Choni invites the family over to the restaurant for dinner and offers to throw the happy couple a big party. But when Lester calls immigration as a supposed favor for Cleveland when he suspects Cecilia's motives, Choni blames Cleveland who denies making the call. After Junior tries to protect Cecilia by running off with her and getting married, Junior moves out of his family's house to live with Cecilia but she realizes he is just a kid and later admits they are both too young to be married. Junior offers to remain married to prevent her deportation and Cecilia continues to work for her aunt while they live apart.
Cleveland notes that while Choni claims to be Mexican she has a Puerto Rican accent which Choni claims she got from attending college in Puerto Rico, although she failed to get an education there.
In "There Goes El Neighborhood", Choni and her family move into Cleveland's neighborhood. Choni is still at odds at Cleveland for nearly getting her niece deported and accuses him of being racist towards Mexicans and decides to teach him a lesson by upstaging his Superbowl party with one of her own. Cleveland becomes upset but comes to realize that maybe he doesn't know anything about Mexicans and asks Choni to educate him by subjecting him to Mexican culture.
Choni's plan is a success as Cleveland becomes completely enraptured in what he has learned. When Choni's babysitter cancels, she asks Cleveland to fill in for her and he agrees. However, Cleveland loses Marco and brings home the wrong Mexican child. As they search for him, they discover him at a chicken auction where Choni turns out to have much in common with the stereotypes Cleveland believed her to have and Choni turns out to also have many of her own stereotypes about blacks. They both admit they have much to learn about each other but Choni still doesn't like Cleveland.
Choni appears at the ceremony when Cleveland and Donna renew their wedding vows in "Here Comes the Bribe".
In "California Dreamin'". Gina puts together an elaborate production of stand-ins including Cecilia & Choni to convince the Brown family that Cleveland has returned home from Los Angeles and they should do the same.
Choni is voiced by Rosie Perez.