Imperious

 

In her last year at Hogwarts, Hermione sat in the Slytherin common room, dressed in the familiar green garments of the house.

Just last year the dark lord had tasked Draco with putting Hermione under the imperious curse. Without Harry realizing, she started working for the Dark lord. She actually used a spell to transform Harry into a stone statue. Now, he was nothing more than a Horocrux cursed object.

Hermione, still under the Imperious curse, attended the last year as a Slytherin. While under the curse, she was vile and evil, and she was there to do both, the dark lord and Draco’s bidding.

What about Ron and the Wesleys? Well Hermione got rid of all of them. But he used a transformation spell on Ron followed by an obliviate to erase his memory.

Ron now works as a fancy escort in London. Apart from her signature red hair, it would be almost impossible to know that beautiful girl was once Harry’s best friend.