Kalua Shuzen is the older sister of Moka and Kokoa with a kogal persona and the second oldest in the Shuzen Family. Carrying a child-like personality, Kokoa is deeply afraid of her and claims Kalua is the best assassin in the Shuzen Family, but ironically hates to hurt others, the reason why she cries whenever she kills. Her earrings acts as limiters, akin to Moka's rosario; once taken off, Kalua has access to further transformations that allows her arms to develop razor-sharp bat wings. According to Yukari, all vampires were able to take forms of other animals, but due to a vampire's vanity of beauty over form, this is considered a forbidden technique. She is also "Charmed", meaning that she feels no pain and can ignore injuries easily, but in the end could die once it wears off. Kalua could have easily killed Moka in their battle, but tried to hold back because of the love for her sister. She is one of the most powerful yōkai encountered by Tsukune in the series, even surpassing the power of Kuyo and Hokuto.
Kalua first appears in the Land of the Snow Fairies, hired by the Fairy Tale organization to assist Miyabi and kill everyone, and fought against the Newspaper Club, decimating them until Inner Moka showed up. She removed her one of her two rosarios and fought her using her awakened form, only stopping when Miyabi stepped in. Kalua later appears in the Land of the Snow Fairies again, but this time to inform Kokoa and Ruby of Fairy Tale's motives. She is then later seen at the main base of Fairy Tale, happily watching Moka's arrival. However, she still fears having to attack her sister again on orders. Similar to her sisters, Kalua's name is perhaps a pun on the Kahlúa drink.