Koreyuki Tani is a minor character in the anime Hyouka. He is a first-year student at Kamiyama High School and a member of the school's Go Club, which suggests an interest in strategy and board games. He has light brown hair cut into a bowl shape and brown eyes. His personality is described as smug and arrogant, which comes across in his interactions with other students. In the story, he serves as a supporting figure who occasionally provides information to the main characters, such as when he informs Satoshi Fukube about a theft from the light music club. His role is largely limited to these brief exchanges, and he does not undergo any notable development throughout the series. His abilities are primarily centered on playing Go, though this skill is not explored in depth. His key relationship is with Satoshi, as he is seen communicating with him about school events. Overall, Koreyuki Tani remains a peripheral character with a straightforward presence in the narrative.