Unicorn's Meal Preference

Listen up, you, the so-called Unicorn Princess. You know, the one who probably thinks glitter is a food group, this is how it works: The joke plays on the word "hay". It's a classic pun, where "hay" which is food for horses sounds exactly like "hayyy" when said in an exaggerated way, therefore, it implies that unicorns eat "hay" too, but they are being silly about it. Get it now?