Ultimate Muscle Roller Legend

Fair warning here, this video is NSFW. And not because it's completely insane...

But it's actually really normal and makes a lot of sense if you read the YouTube description:

Deep in the forest lived Billy and his charming companions. They peacefully honed their bodies and listened to music there. But a wave of development came upon the forests. One who would turn all to road. Kagamine Rin had come. Billy must stop the construction before all is turned to road.

Yeah, OK... Maybe not...