She is a math teacher at Todo High School. She is married with one daughter and is pregnant with another. She and her husband work together. She is close friends with Minato Sakurada, and she doesn't plan to give birth until her child is five years old. Her belly is very large now. Every time the baby moves, her stomach shakes violently, but she's gotten used to it. Ruriko has a friendly and serious personality, often giving advice to students who are confused by her teaching until they understand.