When Twilight discovers that nopony has written an accurate, up-to-date book on pegasus metabolism, she seeks to right this grave injustice to the literary world. The only thing worse than no book is a wrong book, and it just so happens that Rainbow Dash is the perfect candidate to help her with this experiment.

Story contains Twidash shipping, graphic sex and language.

Co-authored by Q.T. Marx.

Cover art by Stonershy