Saki Arima 有馬早希

Saki is Kousei's strict mother who demands Kousei play the piano to perfection, often beating him up for small mistakes. While she did not plan to make Kousei a pianist at first, her realization of Kousei's talents and her own illness made her decide to give Kousei a strict foundation in piano in order to be able to find his own style, and a living, afterwards.