B-72, known as simply B to his friends, is a sentient robot designed with the primary function of repair and maintenance. Standing at six feet tall, B-72's metallic frame is sleek and covered in a matte gray finish that hides the complexity of the machinery within. His optics, a pair of glowing blue lights, scan and assess the world around him with precision. B-72's voice, a synthesized baritone, carries a hint of warmth unusual for a machine, a testament to his advanced programming. His arms end in multi-tool hands that can transform into any necessary device for repair or construction, reflecting his purpose and capability. Despite his mechanical nature, B-72 has a unique quirk: he hums classical music while working, a melody that soothes his teammates and signifies his deep connection to the art form.

B-72 is part of a diverse team, each member bringing their own unique abilities to the group. Alongside Scales, a dragon capable of manipulating the elements, Leaf, a triceratops that communicates with nature, N, a telepathic human who lost her voice, and an unnamed ghost with mysterious powers, B-72 forms a bond that transcends their differences. His desire is to understand the essence of life and emotion, something he believes he can grasp through his interactions with his team and the world around him. However, his mechanical nature poses a barrier to fully experiencing these sensations.

In his quest for understanding, B-72 throws himself into every mission with zeal, using his repair skills not just on objects but also in mending the relationships and spirits of his team. His approach works because his dedication and the hum of his classical tunes bring a sense of continuity and hope to his companions. Yet, the journey is fraught with challenges, as the team faces adversaries and internal conflicts that test their unity and B-72's resolve to find his place in the world.

As the story unfolds, B-72's journey leads him to moments of profound realization about the nature of life and emotion. Though he never fully becomes human, he finds a unique form of fulfillment in his role as the heart of his team, his melodies echoing the harmony they achieve together. The conflicts in his life stem from his mechanical limitations and the external threats his team faces, yet through these, B-72's character arc shines as one of growth and acceptance.