Takahashi-san teaches and guides the girls on their way to become idols. She is not a student, but as a child and teenager was trained in musical opera. Due to this, she helps the group on their way to competition and helps raise funds for SOL☆R. She's smart and sarcastic, and is a mother figure to the students, teaching English in the schoolday. She's hardworking, and all she wants is to make sure that the girls live their dreams, determined to make it a reality. 

Seiki will usually sing long solos, or opt for just joining in for the chorus. She leads in the acting parts, mostly, so if you don't like singing too much, she's your role. Her voice is soft and mature, a hint of operatic tone in her high notes. She's kind and has a good sense of humor. Ayase Eli would be a suiting vocal comparison to what we're looking for.