Yuusuke Igarashi  

, 五十嵐 祐輔

One of Kaes classmates, Igarashi, is both popular and dependable. He's part of the football club and fits the description of a "boy next door" type character. Kae frequently pairs him with Nanashima in their interactions, showing strong support for their relationship. His name, written with the character for "5", makes him the "5" in Kaes ship name for him and Nanashima 5x7.