Age: 16

Ryuunosuke is a second-year student of Suiko. He is the resident of room 102 at Sakura Dormitory. He is a hikikomori who rarely leaves his room and usually communicates with others through cellphone messages and e-mails. To reduce the need to communicate with others, he has written the "Maid" program. He is an expert of computer programming and contributes lots of useful advice and information to Sorata for the latter's computer game. According to Ryuunosuke, his ultimate goal is to make Maid become a real human.