Kiyomi has black hair in a bobcut and dark-colored pupils. She wears the Seikyou Academy uniform as is (i.e. she does not wear the school's blazer) and wears short white socks. Kiyomi also wears a hairband with a wavy design on it.
According to Sasaha Sahara, Kiyomi's personality has changed since she started hanging out with Nao. She becomes considerably unfriendly towards other people, especially those who stay under the Six Year Sakura Tree, and she is only seen happy when she is with Nao. However, Nao's presence is not a guarantee of Kiyomi's cheerful personality at times, as Kiyomi has been seen slapping Nao when the latter makes a mistake.