Akari is Kaho's twin sister. The two are cohesive. For instance, finishing their sentence one another.
Both Kaho and Akari are willing to defend Maya when they engaged in a commotion with Setouchi's students.
Kaho and Akari are on good terms with Hanayama. The two try to revenge for her sake when Hanayama is defeated by Mio, Kotone, and Sayaka.