TV-Series
Description
Dera, whose full name is Ryuu Tadera, is a central supporting character who serves as the current head of the Tadera clan. This family holds the hereditary role of acting as the designated liaison between the isolated Higashi village and the outside world. To fulfill this duty, Dera often travels under the guise of a traveling merchant, bringing goods, medicine, and other necessary supplies to the mountain settlement. Before taking on this role, his background included work as a seasoned mercenary, which has given him extensive knowledge of modern tactics and a wide range of firearms.

In terms of personality, Dera presents himself as an easygoing and free-spirited individual, often coming across as a dependable older brother figure. He has a casual demeanor and a noted fondness for gambling, but beneath this laid-back exterior lies a cool-headed and highly capable operative. While he typically appears relaxed, he consistently rises to the occasion with remarkable resolve and effectiveness whenever a serious situation demands action, making him a deeply trustworthy ally.

Dera’s primary motivation and role in the story are to protect Yuru, the male twin of a powerful set of siblings. When the village comes under a brutal assault, Dera is the one who rescues Yuru and takes on the responsibility of being his guide and combat protector as they flee into modern society. He is instrumental in persuading Yuru to form a contract with his two powerful daemons, Right and Left, which is crucial for the boy's survival. Following the attack, he devises a plan to keep Yuru hidden, which includes proposing to his partner, Hana, that they pose as Yuru's adoptive parents to blend into the modern world without raising suspicion.

His key relationships are central to his function. He works in a close partnership with Hana Danno, who is the other half of the Higashi village retainer pair. While Dera handles the village liaison duties, Hana typically remains on the outskirts as his support and transportation. Together, they act as Yuru’s primary protectors and mentors in the unfamiliar environment of the lower realms. The story also reveals a complex family connection, as Dera encounters a character named Ken, who is identified as his half-brother. Their father, the previous head of the Tadera clan, was involved in helping Yuru’s parents escape in the past, adding a layer of hereditary duty to Dera's motivations. Throughout the narrative, Dera serves as a source of exposition, explaining the history of the Kagemori clan and the dangerous prophecy surrounding the twin birth, which involves the powers of Break and Seal.

While his core personality remains steady as a capable and loyal guardian, Dera’s development is tied to his past. He is a seer, meaning he possesses the notable ability to see daemons, which most humans cannot perceive. This ability, combined with his mercenary combat skills and strategic foresight, makes him far more than a simple merchant. He is characterized by a sense that his actions are calculated, with hints that his own past and the destruction of his former daemon pair might be tied to larger conflicts, adding a layer of hidden depth to his seemingly relaxed nature.
Cast