Okay so, i saw this post by Sadamoto https://twitter.com/Y_Sadamoto/status/626710899609350144 and could tell it was cropped from a full image, and even though its from 2015 this is the only result image searching gave me, the pic in some nico nico cover. If anyone can find it in higher res and without the url that would be amazing. Its such a nice work. The thing it's actually from is called "曲:古畑ミケ 絵:貞本義行 CD"