Sachiko Hisatsu (久津 幸子 Hisatsu Sachiko) is Ken's younger sister. She is kidnapped by Mele on her birthday as a bargaining chip to obtain the SoZyuTo from Ken. Long poses as Sachiko to inform Ken of the kidnapping. Although she is Ken's younger sister, she will not hesitate to keep her brother in line when he starts arguing with somebody.