A girl who reincarnated as a hidden final boss of the RPG otome game Light Magic and the Hero. Yumiella is stoic with a phlegmatic facial expression, which often leads others to be scared and distance themselves from her. She remains logical and approaches situations with a smart and unusual way of thinking that others may not consider or fear. She struggles with social interaction, which includes understanding and building relationships. However, she is a resourceful and smart problem-solver, finding creative solutions to the challenges she faces.