Why would you even read this manga if you're hoping Aikawa is a girl? There's plenty of vanilla romances out there which will deliver this exact thing.
Besides, I direct you here:
http://www.mangainn.com/mangas/1188/...1_00_39_41.jpg
http://www.mangainn.com/mangas/1188/...1_00_39_41.jpg
I don't see how you can see these pages and still hold on to a ray of hope that Aikawa is a girl.
I also heard a rumor that the author specifically stated on twitter that Aikawa is not a girl, but, I don't have a source for that. Would be nice if somebody could confirm/deny.