
Quick answer — Mai Mochizuki voices Kayama in O Maidens in Your Savage Season, Yuuki Tsuji in Liar, Liar, Museum Clerk in Shachibato! President, It's Time for Battle!.
Mai Mochizuki voices Kayama (O Maidens in Your Savage Season), Yuuki Tsuji (Liar, Liar), Museum Clerk (Shachibato! President, It's Time for Battle!).
Kayama is voiced in Japanese by Mai Mochizuki.