Rao, introduced as Sheriff Rao, serves as a main protagonist in Sand Land: The Series. Before the events of the series, his real name was General Shiba, a legendary superstar of the Royal Army revered as the genius soldier who saved Sand Land. He was ordered by Supreme Commander Zeu to lead his troops against the Picchi, a supposedly dangerous race creating an explosive device. In truth, the Picchi were a peaceful people developing a water-producing machine, and Zeu orchestrated the attack to simultaneously eliminate Shiba and his loyal troops while destroying the Picchi. The resulting explosion, fueled by Aquanium provided to the Picchi by the Royal Army, wiped out Shiba's forces, his home, and his wife, the actress Ms. Terrier. Shiba survived but was consumed by guilt and rage upon learning the truth thirty years later. He adopted the name Rao and retreated to a small, remote town, becoming its sheriff and dedicating himself to maintaining order and securing water for its citizens. His primary motivation is to provide water and freedom for the people suffering under the king's monopoly, a goal born from his past failures and a desire for redemption. Rao is an elderly but highly capable human. Despite his age, he possesses extensive combat experience from his time as a general, including expert tank operation and strategic leadership that allows him to quickly overpower the king's army. He is practical and serious, sometimes rigid in his beliefs about human-demon relations, but he gradually learns to trust and work alongside demons. His key relationships are with Beelzebub, the demon prince whom he first approaches for help and who becomes a close ally nicknamed Beelz, and Thief, Beelzebub's companion. Together, they form an unlikely trio that searches for the legendary lake. Throughout the journey, Rao's character develops from a wary human sheriff burdened by his hidden past to a more open and resolute figure who confronts his guilt and directly opposes the king's tyranny.