Naoki Kuroi

Tatsuki's little brother, who appeared later in the season. He's a street-smart, outgoing, but good-hearted boy who like his brother, thinks of himself as a ladies man. He used to have a crush on Ran, then Miyu, and then to Sayo, until he found out that Sayo and Masato had been dating ever since the beginning of junior high! At the end of the TV series, he has a crush on Kasumi. In the manga, he was so optimistic that he had crushes on Ran, then Sayo, then Miyu, then Aya! He's a pro skateboarder and carries around a skateboard all the time. Nevertheless, he's cool yet a bit weird, just like his brother. He works at their father's ramen shop every now and then, and someday wants to run the business.

At first Naoki is upset that Tatsuki will not take over the business but Tatsuki tells Naoki that he wants to follow his own path.