「僕の顔は半紙じゃない…」 "My face isn't a sheet of paper for calligraphy..."
Heh. Anyway, Pixiv tags confirm it to be Akyu. I'm pretty sure it's explained why she has long hair in the description and tags (or at least, reference to it is made) but I'm not positive I understand it. I've seen at least one other pictures of Akyu with hair like this, though.