There's a whole series of this, from 1 until 6, and i've only found 1 and 6, if anyone has 2-5, it'll be greatly appreciated, thanks!
Info on all 6 can be found on the artist's pixiv:
http://www.pixiv.net/member_illust.php?id=2411
Info on all 6 can be found on the artist's pixiv:
http://www.pixiv.net/member_illust.php?id=2411
