Final Fantasy XIII
Hope Estheim is a player-character from Final Fantasy XIII. He is a young boy from Palumpolum who, while on a trip to Bodhum with his mother Nora, is caught up in the Purge. After they're rescued by Team NORA, led by Snow Villiers, Hope becomes worried as Nora volunteers to help the rebels fight back against the Sanctum.
Hope watches the ensuing struggle from afar alongside Oerba Dia Vanille. To his horror, he sees his mother fall to her death. In his shock, Hope blames Snow for what happened and travels with Vanille in order to meet up with him. When they catch up, they quickly meet up with Lightning and Sazh Katzroy as well. Hope, overwhelmed, watches as Lightning, Snow, and Sazh take on a fal'Cie, but in the end, he and the others are all branded as l'Cie and are forced to go on the run.
Initially, Hope is an immature boy who tags along in order to get revenge on Snow and make him pay for his mother's death. As the story progresses, however, he matures, and his desire for revenge is soothed as he travels with the others in their pursuit of their focus and works with them to find a way to escape the fate of the l'Cie.
Final Fantasy XIII-2
In the sequel, Hope is non-playable but an important character.
Serah travels forward in time to the year 10 AF and finds a now twenty-four-year-old Hope working as a head academy researcher investigating paradoxes. He helps Serah and Noel Kreiss on their quest and constantly provides them with helpful information. He is always accompanied by his assistant Alyssa Zaidelle.
As the story progresses, he starts the New Cocoon Project, with the goal of saving humanity from the crash of Cocoon on Grand Pulse, by building a new shell for the people to live in.
In the Paradox Ending, "The Future is Hope," Snow arrives and tells him that he will be assassinated in three days. It is not yet confirmed if this will be picked up in a possible DLC or considered canon in the upcoming Final Fantasy XIII sequel, Lightning Returns: Final Fantasy XIII.