Tsutomu Yamaguchi  

, 山口ツトム

Mikako's childhood friend who lives next door and attends Yazagaku is deeply in love with her. Over time, he searches for his passions and hobbies and eventually becomes an apprentice to Mikako's father, learning photography. He shares a striking resemblance to Ken Nakagawa from "Tenshi Nanka Ja Nai," who is also the lead singer of Manbou and often causes confusion among fans due to his similar appearance. He is frequently referred to as a monkey by Mikako. Along with Ayumi and others, he establishes Akindo, a street market shop/club. Additionally, he appears in Paradise Kiss as Yukari Hayasakas photographer.