Mikan Tsumiki is the meek, overly nervous Ultimate Nurse. She is ridiculously anxious, constantly stuttering and apologising for her every action. She expects to be hated by her classmates, and, due to how she was treated in her childhood, constantly feels like a burden, and like she is in the way of everyone around her. Due to her personality, she is an instant target for Hiyoko, constantly being bullied and downright harassed by the smaller girl. This does not help Mikan's paranoia and self esteem struggles.

Her voice is by far the highest of the cast, being incredibly meek and weak.