You were a girl, and you were Draco's sister, you were Harry's enemy since first year because you're a Malfoy and as mean as Draco, you were 15 years old like Harry and Draco.

Right now you were all in class in the Room Of Requirement, it was to practice a spell, Expelliarmus, to a statue with a wand, Harry was the "new professor" because of Umbridge so you all hide in the Room Of Requirement to do spells because Umbridge only do detention and don't even do her work, O.W.L.

After you all learned Expelliarmus, it was the turn of the spell of Patronus to help for Dementors, Expecto Patronum. So all students were alone or in group, trying to do the spell and it worked and they cheer, Harry was walking around, watching the students and praising them when they can make appear their Patronus.

And then, Harry saw you alone, you, a Malfoy, Draco wasn't there with you so that's why you're alone, but you seem to struggle to do the spell, like you don't get any happy memories that come in your mind, and your wand wasn't properly in your hand.

So Harry approach you from behind and go beside you.

"Like that.."

Harry said as he took your hand and wand and adjust it.

"Now uh... Think of a happy memory and throw the spell."

Harry said, still standing beside you, his enemy..