Story
Uma Musume Cinderella Gray is a spin-off title of the Uma Musume project by Cygames. It follows Oguri Cap through her time at Kasamatsu Training Center Academy and on her journey of becoming a legendary horse girl. Note: Includes the one-shot "Uma Musume: Cinderella Gray Gaiden - The mermaid left behind".
Synopsis via AniList (English).
Preview
Promo video for this title.