The Secret Service: an elite military unit especially trained to protect the ponykind from every kind of threat under the protection of secret identities.

Agent Lyra Heartstrings of the Secret Service doesn't belive in humans, she just pretends to for her identity's sake. She lives a happy life being secretly a hero, until Anthropology fan Sweet Pea turns Lyra's entire world upside-down when he reveals a dark secret about herself. A secret she wished she never knew.

Tribute to Anthropology by JasonTheHuman.
ONE OF THE BEST STORIES EVER, THANK YOU FOR THAT JASON