Mayu Anjou

安城真由
One of the two girls who could have been Yousukes sister. She is skilled at the violin and plays it at a professional level. She is really close to Ayu and likes that Yousuke tries to be a big brother to her. Of the two girls she is the only one that calls Yousuke quotoniichanquot lit. quotbig brotherquot. The manga also shows that she is more caring than Ayu towards Yousuke. source: Wikipedia