I heard this song for the first time when I was in elementary, playing Dancing Origiri, for some reason this stuck in my head for quite a while (even until now). I don't even know how to download or search for this song because I was too dumb to use computer back then (I was about 7 at that time). I nearly cried when I found this video just now.
There was a more recent recent version uploaded a couple months ago. It's sad it got removed :( But I got the time to make a piano arrangement of it eh eh eh...
progressive trance with high emphasis on the piano artists like paraoka, shiki, wa., cres, shiraishi, void, and a bunch of other BMS artists make music just like this. i know this comment is 11 years old, but check them out if you haven't!
@MinecraftNirbil There actually are a number of custom DDR/Stepmania charts for this song. They're not too hard in an absolute sense either - they're certainly doable by anyone with some practice.