Translation: Sonic in a "Kero ⑨ destiny" Parody. This September 2008, every Sonic fans drew for the official illustration contest. On the other hand, I drew for this animated video.
If you have a Niconico douga account, I highly recommend viewing this work at its original location: http://www.nicovideo.jp/watch/sm4904563 The animator is known as ina☆ at Nico. She may also be found at pixiv as i if you are interested in seeing more of her work. This is an animation trend that's been seen at Niconico douga a long while ago. Sonic just joined it a few minutes ago. The song in the background is "ケロ⑨destiny" (Kero ⑨ destiny), a remix of Suwako Moriya's Theme from Touhou's Mountain of Faith - Wind God Record (Touhou Fuujinroku). Japanese Internet culture (and language) is recommended to enjoy this video to its fullest though you may be able to enjoy the silly animation nonetheless. Note that the Japanese subtitled lyrics do not follow the actual song lyrics. As it is a parody, they are Sonic interpretation of the dong. A translation may be updated shortly.
I am not the author of this work. This is merely a Sonic hand drawn animation channel. If you are the creator of this video, feel free to ask for it to be taken down from Youtube.