TV-Series
Description
Seventeen-year-old Subaru Sengoku, operating under the hero name Mr. Black, is a NEXT with the power to generate resilient barrier fields resembling floating holograms. He previously served as the superhero Hello Goodbye in his hometown of Panjourney before relocating to Stern Bild City after achieving high scores in Hero TV's recruitment examination.

This relocation triggered a mandatory hero name change to Mr. Black and his assignment to the Jungle sponsor company. Subaru holds strong ideals about heroism, prioritizing saving lives and defeating villains above Hero TV's commercialized aspects like merchandise sales and ratings competition. This perspective causes friction with the established hero system and his colleagues, particularly when he questions Barnaby Brooks Jr.'s motivations for continuing hero work after achieving revenge.

Partnered with Thomas Taurus (He Is Thomas) under Hero TV's buddy system, their alliance begins conflict-ridden due to Thomas's solitary nature and Subaru's frustration at being relegated to a support role for someone he perceives as lacking genuine heroic motivation. Early missions expose their dysfunctional dynamic, including an incident where Subaru's desire to outshine Thomas compromised Origami Cyclone's undercover operation during a drug bust targeting Veron Urbano. Another failure occurred when Subaru hesitated during an arrest, leading to a civilian injury and Thomas's violent retaliation against the criminal, resulting in Thomas's suspension.

Subaru attempts to mend their partnership by researching NEXT powers and confronting Thomas about his reluctance to cooperate, but Thomas rebuffs these efforts, emphasizing his preference for working alone. Their dynamic shifts during confrontations with the villains Mugan and Fugan. Rock Bison convinces Subaru, Thomas, and Magical Cat to prioritize escape over futile resistance in one battle. In a later clash, Subaru protects Thomas from Fugan's attack, declaring that Thomas's offensive power necessitates protection even at personal cost, which results in Subaru sustaining a leg injury. Thomas expresses gratitude afterward, though Subaru downplays the act.

Later, Subaru orchestrates a reunion between Thomas and his long-lost younger sister, Ruby Taurus. He facilitated their meeting at Fortress Tower during an attack by X, guiding Thomas to her location. Subaru revealed this act stemmed from a desire to repay Thomas after a past failure where his inability to maintain a barrier during a joint attack accidentally knocked Thomas unconscious, allowing a criminal to escape. Witnessing the siblings' reunion moved Subaru to tears as he acknowledged Thomas's hidden pain. Following this, Thomas departs Stern Bild to become a hero in Pleiades, leaving Subaru to continue his hero career solo at Jungle.

Throughout these events, Subaru evolves from a brash rookie focused on individual recognition to a hero who understands the value of teamwork and protecting others, demonstrated by his self-sacrifice for Thomas and his role in reuniting the Taurus siblings. Despite maintaining his critical view of Hero TV's commercialism, his actions increasingly align with his stated ideals of prioritizing lives and justice.