Udonko Kondō is Yuri Oshimoto's classmate and a reporter for the Kameido High School newspaper. She fixates on the tennis club's activities despite their minimal focus on actual tennis, prioritizing sensational or trivial details in her reporting, revealing unusual observational priorities. She lives with her family: her older sister, Annenkov Kondo, works as a bhikkhu (exorcist), and her grandfather manages an udon shop. Udonko possesses auburn hair, aubergine-colored eyes, wears glasses, and styles her hair in pigtails. Beyond reporting, she occasionally joins the tennis club's unconventional adventures. Udonko exhibits the anomalous ability to store improbably large objects—like construction vehicles—within her pockets, a consistent trait. Her involvement spans multiple seasons and media, including performing the theme song "Gluten Elegy" for the series' eighth season. Her role and established traits remain consistent across documented spin-offs, films, and other official media.