As a child, Chiriko was a shy girl and a member of the Super Peace Busters. Now, she is enrolled at an elite school with Matsuyuki. Currently, she is ranked fourth in her class. She is serious, stoic, and cocky. Upon meeting with Naruko, Chiriko insults both her and her friends; however, she has since made amends with Naruko. While the other members of the Super Peace Busters have fallen apart, Chiriko and Matsuyuki have remained friends after Menma's death.

Chiriko is shown to have feelings for Matsuyuki; however, he does not reciprocate her affection at first because he is still in love with Menma. Matsuyuki's heart belongs to Menma. He asks Naruko out and Chiriko overhears this conversation and is devastated. Chiriko and Matsuyuki are shown dating after Menma disappears.