I wonder how she is able to make a fist with her right hand with that nails.

Is "Boeee" (and this pose) a reference to something else? I've seen it in a Hatsune Miku video as well.
http://uk.youtube.com/watch?v=UnpSAMnGi78

With great care.

'Boeee' is probably be a reference to the Doraemon character Jaian's horrible singing. The character is listed on Danbooru under the name goda_takeshi. I don't think the pose is directly related. You can find some examples at pixiv of boeee being tagged with Jaian's name.
http://www.pixiv.net/member_illust.php?mode=medium&illust_id=1150936
http://www.pixiv.net/member_illust.php?mode=medium&illust_id=9862

Or alternatively sounded as hogeee or bogeee:
http://www.pixiv.net/member_illust.php?mode=medium&illust_id=30703
http://www.pixiv.net/member_illust.php?mode=medium&illust_id=297386

Perhaps her talons are retractable.