Aiko Esther Cerviche appears in Fan Movie 4. She is World G counterpart of Aiko Esther Cerviche. She's Kazuma's adopted sister. Aiko forced Kazuma to have tea party with her. Aiko forced him to wear a kimono (for girls) and made him wear lipstick. She even made Kazuma wear different dresses which Polly and Francine find him cute. Despite what she did, both Kazuma and Aiko love each other and care about each other. She's very nice to her brother. Later, when Kazuma did his master of disguise round, he wore dresses and he thank her for the lesson. Aiko got upset when she heard her brother got kidnapped. When Kazuma came home, she breaks down crying with joy and he returns home.