To whoever it was who switched 'perfectly round' to 'maruku naru', you are damn fast and awesome for it.
I'm trying to get the artist's name: this is their profile on pixv - http://www.pixiv.net/member.php?id=503063 - and as far as I can get out of google translate (yes, yes, shoot me now...) they're called Tta. Google Translate being Google Translate I'm entirely trusting that; can anyone confirm?