A high school student and the last descendant of a demon-fighting hero clan. He is forced into a master-servant contract with Maria and Mio, becoming their master and forming a close bond to help them overcome future challenges.
Step-siblings bound by a life-saving pact, evolving from protective guardianship to deeply intertwined combat partners and romantic tension.
Step-siblings with a master-servant dynamic; Maria's betrayal in S1 leads to redemption and shared tournament battles in S2.
Basara carries forward his father's legacy and supernatural abilities, driving his motivation in the final arcs.
Childhood friends with unresolved romantic tension; forge a master-servant pact in S1 and maintain close emotional entanglement through S2 school events.
Mio's feelings for Basara mature from duty to genuine care, influencing her combat and personal choices.
Classmates bound by a master-servant pact; evolve from cautious allies to trusted combat partners supporting Basara's circle.
Jin's legacy serves as a crucial narrative device, empowering Basara during the season's climax.
Hidden manipulator using magic to control others; confronts Basara during the sports festival, revealing antagonistic motives and binding him.
Former demon lord acting as a protective mentor; shifts from distant figure to active ally and reunion anchor across both seasons.
Classmate and white-masked observer who provides crucial pact information; maintains a supportive but secondary role throughout S1.
Zest acts as a disruptive force during the captivity arc, altering the balance of power between captors and captives.
Maria and Basara maintain a relaxed step-sibling dynamic that contrasts with the more intense contracts.
Their date represents a rare moment of normalcy and social bonding outside of supernatural conflicts.
Explore the full interactive character relationship map of The Testament of Sister New Devil