Iharra Materu

     "You are not worthy enough to become                               one of us." Materu is one of the minor character in Koi no Uta but eventually have an important role at the end of Season 2. He never appear in Season 1, only to be mentioned.

Appearance
He and Kazuki really look very similar to each other; the only noticeable difference being their personalities and hair colour.

Personality
Materu have the same cool aura as Kazuki but tends to change to a dangerous one when talking business.

Background
He was mentioned in Season 1 by Kazuki to be his mother's reason of death and Kazuki was actually trying to find him, leaving Sakura confused with her feelings.

In Season 2, he make his first appearance when Yunoki introduced Sakura to him. He immediately ask her to break up with Yun and then left.

He appeared in Kazuki's flashbacks, when his mother told her story with Materu.

Hanamichi Kazuki
Kazuki is Hanamichi Sakura and his first son.

Sakurairi Nakamura
He is disapproving the relationship between her and Yunoki but never say anything about her relationship with Kazuki.