On the train ride to their sixth school year Hermione and Harry decide to be a couple only to be separated, induced by potions and controlled by Ron and Ginny two month later for the Greater Good. All this was planed and orchestrated by Dumbledore. The control potions required frequent sexual actions of the controlled person. In the summer Hermione uncovers this and ran together with Harry away. He marries her to protect her from similar machinations. Because of an outstanding Marriage contract he marries Daphne Greengrass as well. Together they clean the British wizarding world out.
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