Kouki Mikagami  

, 御鏡 光輝

Kouki is a model who secretly enjoys anime and manga, known as otaku. Kirino asked him to pretend to be her boyfriend in order to help Kyousuke understand how she felt when he spent time with other girls. Afterwards, Kouki became friends with Kyousuke and offered him dating advice. However, he also caused problems for Kyousuke, such as giving him an expensive set of adult game figures as a housewarming gift.