Hayakawa Mariko

Yuriko's older sister and the school's nurse. She is also Hikari's best friend. Nowadays, she works as a scientist in W.L.O., Mariko retired from being the school nurse. However, she also works part-time at NOA. She is also the one who does regular checkups for Sarasa, however, for some reason, Arisa doesn't seem to like it.