AUTHOR'S NOTE: Don't judge my writing from this story, I hate it now.
Rainbow Dash, after getting the chance to be part of an adventure with her idol, decides she needs to write a story about her. Daring Do, that is. When she can't think of a premise, Pinkie Pie offers to help with her knowledge of "The Sacred Chalice". And once they're done, Rainbow asks Twilight for her opinion. Rated Teen to stay true to the original content.
Completely inspired by Ninja Sex Party's "The Sacred Chalice". Not linking to it because this is only a teen-rated fic, and their music could probably be considered NSFW. But look it up anyway.
Changeling Sex Party?
That idea's AWESOME!