Masato Kusaka is a major character in the tokusatsu series Kamen Rider Faiz. Portrayed as Kamen Rider Kaixa, he is both an ally and antagonist to the protagonist, Takumi Inui. Highly intelligent and cunning, Kusaka is driven by a personal vendetta and distrusts the Orphnoch, often making morally ambiguous choices. His complex personality and tragic past make him one of the most memorable and divisive characters in the series, significantly shaping the narrative’s emotional and ethical conflicts.