Kanata Iwao is a superhuman with distinctive pink skin, a trait common to genetically modified individuals in the universe of Milky☆Subway: The Galactic Limited Express. He is a young man of short stature, standing at approximately 1.6 meters, which makes him the second-shortest member of the main cast. His character design reflects his rebellious attitude; he typically wears a nonconformist outfit consisting of a purple tank top and matching pants, often adorned with text and insignia that mark him as a member of a galactic biker gang. One of his most notable physical features is his spiky purple hair and the small antennae on his head, which add to his alien appearance.

Kanata's personality is defined by a stark contrast between his public persona and his private self. He presents himself as a boisterous and aggressive delinquent, walking with a crouched swagger and his hands in his pockets to appear more intimidating than he actually is. Despite this tough exterior, he is genuinely weak and often comes across as all talk, earning him the archetype of a boisterous weakling. He has a quick temper and a bad habit of picking fights or escalating situations, which frequently leads to him getting into trouble or becoming the victim of physical comedy, such as being electrocuted. Kanata is also a notably bad liar, often telling blatant falsehoods in clumsy attempts to protect his companion Akane's social image.

His motivations are rooted in a deep-seated insecurity about his own identity and worth. He rebelled against his parents' overprotective upbringing, which led him to join a street racing gang. However, even as a member of the Galaxy Spirits biker gang, he finds himself once again subjected to overprotection, this time from his fellow gang member and superior, Akane. This dynamic leaves him feeling useless and frustrated, constantly questioning his own significance and struggling to prove his independence.

Within the story, Kanata is one of six criminals sentenced to community service aboard the Galactic Limited Express, having been arrested alongside Akane for reckless space driving and speeding. His role in the ragtag group is initially that of a loud-mouthed instigator, but his true value emerges through his hidden depths. When he is not forcing a tough-guy persona, Kanata reveals a high degree of intelligence, particularly with a natural talent for mechanics and engineering. This practical knowledge proves essential for overcoming many of the technical obstacles that the group encounters on the train, as he can understand and repair complex machinery, even in cramped spaces.

Kanata's most significant relationship is with Akane, the much taller and more powerful leader of their biker gang. Their dynamic is a classic "Red Oni, Blue Oni" pairing, with Kanata as the loud and impulsive foil to Akane's quiet and calm demeanor. Despite his attempts to be tough, Akane treats him with the same overprotective instinct he tried to escape from his parents, which is a source of constant internal conflict for him. Even so, they are True Companions; Akane will fiercely defend Kanata from any physical threat, and Kanata will cover for her in socially awkward situations. Throughout the series, Kanata develops by learning to accept his own abilities. While he initially dismisses his mechanical skills and his less-imposing physique, these very traits become what the group needs to survive, allowing him to find a sense of purpose beyond his failed attempts at brute force. His key abilities include his mechanical aptitude and a surprising resilience, as he often bounces back from the physical comedy that befalls him.