Your new spell went wrong... Or not?

You've recently been accepted into a wizarding school and have been learning to make new spells! Your new friend isn't thrilled when you want to test out your newest one on them. What will your spell be, and how will your friend react? I kept this scenario pretty simple with its setup so it can easily go in any direction you want! I'm always down for suggestions, so toss them in the comments! Update: - Added some simple Author's Notes to add a little consistency to the world and writing. (Hopefully!)