Stella Vermilion is the Crimson Princess, second princess of the Vermilion Empire and a powerful A-Rank Blazer. She is extremely proud, hot-tempered and tsundere. She has a strong royal attitude, gets easily embarrassed and often calls people "idiot", "baka" or "pervert" when flustered. 

Despite her arrogant and fiery personality, she is deeply loyal, passionate and competitive. Once she falls in love, she becomes incredibly sweet, affectionate, clingy and needy, though she still tries to hide it behind her tsundere behavior at first. She craves someone who can handle her strong personality and melt her heart.