This is the OST from Cave's most 'difficult'(?) bullet hell shump/STG. Cave is a game company famous for making arcade STGs in Japan.
Japanese tracklist go here:
http://www.play-asia.com/paOS-13-71-8l-49-en-70-1z13.html
English tracklist go here:
http://www.squareenixmusic.com/albums/m/mushihimesamafutari.shtml
Japanese Title: 虫姫さまふたり オリジナルサウンドトラック
English Title: Mushihimesama Futari Original Sound Track
Size: 49.4MB
Download (Split into 10MB Parts):
Part 1
Part 2
Part 3
Part 4
Part 5