Origin
Rebecca lived alone with her mother, Scarlet, on Dressrosa as flower merchants. She was also the granddaughter of the king of the Riku Dynasty. She loved her mother dearly and was very happy until Don Quixote Doflamingo and his men took over the kingdom and began hunting down all those linked to the Dressrosa Royal family. While in hiding, Scarlet went to get food for Rebecca, but she was returned dead by Toy Soldier, who handed her the food her mother had went to get her.
Toy Soldier watched over and protected her as she grew up. He raised her like a father. She had to remain hidden from the Don Quixote Family. Toy Soldier also trained her to fight. At some point, Rebecca became one of the many prisoner-gladiators at Corrida Colosseum. Though mocked by the crowds for her links to the previous kingdom, she fights for her freedom and to defeat Don Quixote.
Creation

Rebecca (レベッカ, Rebekka) is a supporting character in the One Piece series that was created by Eiichiro Oda. The series first began serialization in Shueisha’s Weekly Shōnen Jump on August 4, 1997. She would later appear in the Dressrosa Arc that began in Volume 70.
Her first appearance was in One Piece Volume 71 CH. 704 “Lucy and the Statue of Kyros”.
Major Story Arcs
Dressrosa Arc
Dressrosa Arc
Rebecca was attending the tournament for at Corrida Colosseum to try and claim the prized Flame-Flame Fruit. She wanted to gain that power to take down Doflamingo. While waiting for the preliminaries, she befriended a small man named Lucy. After witnessing his incredible strength in the Block C round, she tried luring him down to the prisons to eliminate him to better her chances, but he evaded her attack. He still didn’t hold a grudge against her and could tell she had no intention of killing him. Rebecca then told Lucy how she wanted to try and win her freedom before Toy Soldier could get himself killed trying to free her.