Because "Yukari holding a giant fox's sealed severed head while a satelite on world tree being thinkered by the Thing from the Addams Family while belts of solid colored butterflies surround the world tree." just won't cut it.
Well the fox head is probably Ran, the world tree is Gensokyo, the planet is obviously Earth, the butterflies are Hakugyokurou and the satellite is the moon capital. The things in the background are probably just nameless generic shikigami/youkai.
