Shinobu Sengoku is a student at Yumenosaki Academy and a member of the idol unit Akatsuki in the Ensemble Stars! series. Known for his ninja obsession and energetic personality, Shinobu often sprinkles his speech with ninja terminology. Despite his small stature and timid demeanor, he is hardworking and deeply loyal to his friends and group. Shinobu's role in the story is to provide comic relief, but he also demonstrates growth and determination as he pursues his dream of becoming a true 'ninja idol.'