Ken Takayanagi, a childhood friend of Azusa "Azuki" Noyama, playfully ribs her about the nickname "Azuki-chan," a jest originating from his elementary-school misreading of her name. His family operates Manruiken, a ramen stall nestled near Azuki’s apartment, where she regularly dines. Though nursing unrequited feelings for Azuki, he grapples with acknowledging Kaoru Nishino’s persistent affection, their dynamic shifting as he slowly lets down his guard after internal turmoil.

A hotheaded baseball player prone to impulsivity, Ken confronts his flaws after unfairly blaming Kaoru for a game loss, sparking self-reflection that culminates in an indirect apology. This moment becomes a turning point, thawing their rapport. His knack for landing in absurdly awkward scenarios fuels recurring comedic relief.

Ken’s father, running the family ramen stall, harbors a past of unrequited admiration for his former teacher—now the school principal—adding subtle complexity to their familial exchanges. While Ken’s mother remains largely absent narratively, his role as Azuki’s irksome yet devoted pseudo-sibling remains steady, despite sparse mentions of a younger brother.

Central to his growth is the evolution from stubbornly fixating on Azuki to tentatively embracing Kaoru’s earnestness, charting a path from immaturity to emotional awareness. His narrative remains confined to the main series, with no expanded portrayal in supplementary media.