Marco Nogata plays a minor role in the story until Tonkichi hires him at the Mabase amusement park. At this park, which is secretly a weapon designed to be used against Medical Mechanica, Tonkichi uses Marco as a test subject for a ride that causes N.O. activity. Due to bumping heads with Hidomi earlier, this causes his newly-acquired N.O. channel to grow bamboo that, when launching him from the ride, winds up inadvertently helping to save Ide and Hidomi from their fall off the MM iron.
Marco is normally quiet and tame. He develops a brief crush on Hidomi when her headphones cause a personality change, finding her new cheerful personality cute and considers buying a gift for her, which leads him to get a job at the amusement park. He did not hesitate to step in to protect Hidomi when she was being observed by a stranger. He has also been a good listener for Goro and believes his claims about fashion trends. He takes a noticeable interest in Ide's "relationship" with Miss Shimazaki, seeming very giddy and excited as he emphatically brags about the maturity of it. His behavior towards Ide's relationship with Hidomi is less excited and celebratory, possibly because he shares a physical attraction to her that was unrealized until her personality change.
Marco is a tall, slender guy with tan skin. He has messy brown hair resembling a fluffy scissor cut, and angular brown eyes and eyebrows. His lips are full and he has a sharp jawline. He wears a white polo shirt with horizontal red stripes, tan pants, and green shoes with darker tan soles. Eye Patch believes his Latin blood and proportions would make him a good boxer.
Marco is hired and used by Tonkichi to test a Viking Cruise ship ride developed by the Bureau of Interstellar Immigration at an attraction park, which is actually a weapon that can affect N.O. channels. After knocking heads with Hidomi earlier, this ride causes his N.O. channel to activate. Bamboo grows out of his forehead, scraping the concrete when the ride does a flip and sending him flying off. He lands under the Medical Mechanica factory where the bamboo begins to flip it over as a robot emerges from his head, distracting Haruko from her battle with Jinyu long enough for her to save Hidomi and Ide as they fell off the tipping iron. He is also later found riding a coin-operated duck ride at the center of the amusement mech when mochi causes it to crack open, suggesting his N.O. channel was also assisting in powering it. This also serves as the transition into the extended credit sequence for the final episode, featuring Marco riding the duck on wheels around the rubble that is Mabase and greeting characters.
Marco and Ide spend a lot of time together and Marco sympathizes with his tough home life. They happen to disagree on Goro's fashion choices. For a brief period, Hidomi's personality change made Marco somewhat jealous of Ide's budding relationship with her. He found her incredibly cute and got a job at the amusement park to buy her a gift, but quickly dropped out of the love triangle when she returned to normal and began pursuing Ide more.
Like with Ide, Marco and Goro have a pre-established friendship. Goro's first interaction with Marco is a debate between Goro and Ide about his skirt where Marco sides with Goro, believing his claims about unisex fashion being "in." When Goro's envy of Ide's success with relationships reaches a boiling point in episode 3, Marco stands by his side while he vents his frustrations. Having witnessed him paying off the girl he tried to pass as his girlfriend earlier and then being ditched by Ide for Hidomi, Marco had an understanding of his frustrations and became his metaphorical shoulder to cry on for that night.
- A conversation with Eye Patch confirms that Marco is of Latin descent.