A quiet bookworm in Usagi's class called Amy in the English adaptations of the series. She is hugely intelligent, with an IQ of 300, and can transform into Sailor Mercury, acquiring power over water. Ami's shy exterior masks a passion for knowledge and for taking care of the people around her. She hopes to be a doctor one day, like her mother and tends to be the practical one in the group. Secretly, she is also a fan of pop culture and romance novels and becomes embarrassed whenever this is pointed out.