At school, before entering the Dark World, Susie appears as a bully. She acts very rude and aggressive toward other students, insulting them and even threatening them with physical violence, such as "eating [one's] face." She does not have any friends and appears to be convinced that everyone hates her. Susie may, however, use this as an excuse to act rudely. When she enters the Dark World, Susie beats up every enemy she meets and is uninterested in being a Hero of Light, even saying to Ralsei that the end of the world is "none of [her] business" and that it "might be kind of fun."

When Lancer compliments her on her villain performance, she becomes excited about finally meeting someone who appreciates her as a "bad guy." After joining Lancer's side and forging a friendship with him, she starts to have fun and be more caring to him. To avoid killing King and hurting Lancer's feelings, Susie changes her ways and obeys Kris's orders, though somewhat reluctantly at times.