A friend of Cecil and Kain since childhood, Rosa eventually fell in love with the Dark Knight of Baron and took up White Magic so she could aid him. She was deeply concerned about Cecil's future after his falling out with the King, going so far as to run after him on his journey.

In the Duelling League, Rosa relies on her impressive array of White magic spells to win fights. With plenty of healing, Blink and Mini to shut down fighters, Berserk and Silence to handle mages, and Holy for massive damage when needed, she has all the tools she needs to win, even managing to get a Heavy Championship and a Godlike upgrade once.