Sumiji Kuroyama (黒山 墨字 Kuroyama Sumiji) is main deutragonist of Act-Age manga series. He is a director and also founder of Studio Daikokuten.
Although he had won various film festival awards overseas, he isn't famous in Japan as a director. He founded Studio Daikokuten to make just one film in future. After discovering Kei Yonagi's talent from an audition, he invites Yonagi to his studio and guides her to be an actress who will leave an imprint on history of acting.