|Japanese name:||水無月 ちか|
A student in her first year of high school, she is energetic and often times finds herself in Kaoru's bed thinking it's her own. She has her own Kaoru doll she carries around and a small book with a picture of the two of them. Chika is one of three members in the Swiming Club; the other two are her friends Natuki Komiya and Chizuru Aizawa.
Chika's given name means "near".
Voiced by: Momoi Haruko