南国原大吾

一馬が転入した学園で知り合い、たちまち意気投合した悪友。
ノリがよく、お祭り好き。悪ノリしすぎて、しょっちゅう伊吹やこよりの制裁を食らっているが、それでもめげない人物である。
ハマっているネットゲームに嫁がいるらしいが、真実か否かは不明。

Spirited and somewhat eccentric, Daigo Minamikokubaru is a second-year student. A classmate, he befriends Kazuma almost immediately on his first day of the school, acquainting him with the campus and even the profiles of some of the girls he meets; jealous of his unintentional success with women. As a sign of brethren respect, he frequently addresses Kazuma "brother". Daigo is the son of the second-year homeroom instructor.

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