It is unknown that he has friends but he does have a girlfriend named Yoshimi Yahagi.
In the Program
After the students wake up in the classroom, Yoji whispers to Yoshimi when Kitano hits Yoji with a piece of chalk. Yoshimi angrily confronts Kitano, Kitano pushes her forehead away with his finger, and Yoshimi sits down. He and Yoshimi are later found hung with Yoji's rope.