Nanami Kosugi is a supporting character in the anime Gingitsune. He is a male student at the local high school and a member of the school's kendo club. He has auburn hair and black eyes. His surname, Kosugi, and given name, Nanami, are written with characters meaning "seven" and "sea."

In terms of personality, Nanami is characterized by a strong dislike for Satoru Kamio, a fellow student who possesses the ability to see the shrine's fox herald. Nanami's animosity stems from Satoru's poor attitude. Despite this friction, Nanami appears to have developed romantic feelings for Makoto Saeki, the main female protagonist who serves as the shrine maiden. He is often cautious around Yumi Ikegami, a classmate who knows embarrassing details about his past and tends to tease him.

His role in the story is that of a supporting classmate and friend who interacts with the main cast through school life and occasional involvement in shrine-related events. There is no documented development arc or special abilities associated with him; his function is primarily to add interpersonal dynamics among the student group.