Cornelio is a villain from Romancing SaGa, acting as a major antagonist in Claudia's storyline.
The current Duke of Loban, Cornelio is married to Matilda, the younger sister of Emperor Fel IV of the Bafal Empire. Since the Emperor's daughter is currently missing (she's actually Claudia, who was been taken on by the Witch of Mazewood to protect her from assassins), because of his marriage Cornelio is the next in the line of sucession to the Bafal throne, and is thus constantly scheming to kill the Emperor and assume the throne.
Neville, captain of the Melvir Guard, is aware of Cornelio's machinations, and is secretly investigating his activities, alongside the imperial knight Gian and the undercover agent Monica. After Claudia leaves Mazewood and arrives in Melvir, Gian and Neville ask for her help in investingating the happenings around Melvir, assigning the adventuer Gray to escort her. Gian ends imprisoned in Loban while investigating Cornelio, but is rescued by Claudia and Gray, who are then forced to flee the empire.
Cornelio would later put a curse upon the Emperor with the help of Saruin's priests, slowly consuming his life. The heroes manage to undo the curse by using the Moonstone, at which point Cornelio asks for help to combat the pirates who had been operating on the Coral Sea, being given control over the entire Imperial Army to fight the pirates, which leaves Melvir open to attack. Not too long after this Melvir is invaded by pirates led by the Butcher and hordes of monsters summoned by one of Saruin's Minions, both of which are implied to actually be working together with Cornelio. Cornelio is never seen again after the invasions are thwarted.