藤倉 優

A maid of the Arima household who sometimes councils Teppei. She had been in an orphanage from a very young age until Isshin Arima took her into his care and brought her up to be an admirable maid. She has sworn to serve the Arima family to show her gratitude. 

She feels privileged to have been assigned as the maid-in-charge of serving Teppei, the next heir to the Arima Group. In addition to her household duties, Yuu is also an expert at computers and is able to type and work at almost superhuman speed. She thinks of Isshin Arima as a parent and develops tender feelings for Teppei, but feels that she is too low in class to be with him. 

Of all the girls, she is the most tender and nurturing and Teppei compares Yuu to his mother. Her route concludes with Teppei Having a vision where he is welcomed home by his parents with a pregnant Yuu./