Puzzling Pink Pecks on a Purple Pony Princess

Twilight likes Pinkie Pie, but she often finds herself befuddled by the mare. A Twinkie Fic.

Twilight loves all her friends, but lately a certain pink pony has been occupying her mind a bit more than usual: thankfully, she knows to keep such feelings to herself.

...So why has that mare been giggling everytime she passes by?