As her name implies, Yumi has a very cool personality. She is a very calm and very serious girl. She gives nothing but one hundred percent when it comes to achieving a personal ambition and will go to any lengths to realize a goal she has set out for herself. For these reasons she could be viewed as stubborn when people present their own personal ideals and values in conflict with her own. While being very harsh at times, she's also very caring underneath her cold exterior. Yumi is only hard on her comrades because she genuinely cares about them and wants the most out of each of them. She is 18.