You have entered Equestria via a black portal. To make matters worse, the portal's properties have made your body able to cast magic spells, much like a unicorn. To ensure that you can be able to control these powers, Celestia assigned you to be Twilight's student.

What a great decision she had made. Throughout your time with her, you developed feelings for your teacher. One night, you ask to sleepover at her house. This night would be the night that would change your relationship to her forever as she tests your willpower.

Image by Mewball.