Twilight Sparkle has faced down plenty of scary things during her time in Ponyville – Nightmare Moon, Tirek, changelings, and even quesadillas. None have come close to stopping her.
But romance? There's a whole galaxy of things to be scared of there. Rejection? Check. Performance anxiety? Check. Fear of not satisfying her partner? Double check. Fear of being embarrassed on behalf of her partner because he failed to satisfy her? Triple check.
But Twilight has friends who love her, and one friend in particular who's going to demolish these fears, come hell or high water.