This looks like it's probably the right page of a two-page image or something similar.

Kalessin said:
This looks like it's probably the right page of a two-page image or something similar.

Doesn't seem so; the artist didn't state that this is part of a book, and none of his works include this image. But for some reason the one uploaded here is a horizontal flip of what he has up on his pixiv:
http://www.pixiv.net/member_illust.php?mode=medium&illust_id=6618052

He mentioned that he made some changes to the original, so I'm guessing the flip was one of them since these two versions are different.

Well, it's odd image if it's not part of a greater whole - what with her cut off and all.

Rather than it looking odd because it's cut off (because there are a lot of images that do this), I think it looks odd to most because of the large amount of negative space on the right.

She holds a devilish flower cause it has pentagram.

Ponnkun said:
I think it looks odd to most because of the large amount of negative space on the right.

It might be a matter of focusing. Maybe the focus of the picture isn't the girl...