This is a mini-album that was released at Comitia117. As far as I can see, it's a doujin anime/manga event. Unfortunately, I can't find it in the events listing. Can anybody consider adding it?
Code:
https://www.comitia.co.jp/html/117.html
There really isn't a lot of information available for this release, but I managed to find a somewhat reliable Romaji track-list.
Code:
http://www.generasia.com/wiki/Slow_Light,_Slow_Glass