After the battle at Hogwarts, Harry, Ron and Hermione had returned to complete their seventh year alongside Ginny; though Ron and Hermione were not dating, Harry and Ginny were. Lupin did not die and was immediately appointed Defence Against the Dark Arts teacher, along with Sirius.
It was Monday afternoon and the four friends were in their potions class which was the last lesson of the day. Harry and Ron were paired to make an 'Exploding Fluid' potion, whilst the girls were also partnered together. Ron, being tired from a weekend of hard partying, crudely remarked,
"Why do we have to make this bloody exploding potion, anyway?" Upon hearing his statement, their potions teacher (newly appointed Professor Drover,) gave Ron a sharp tap on the head with his textbook.
"None of that negative business in my classroom Weasley, or else you will find yourself in detention! Do you hear me?" Ron mumbled a quick apology and, in his frustration, threw a bundle of erumpent liquid into the cauldron.
"Ron, wait!" yelled Harry, but his efforts were in vain.
Suddenly they were deafened by a large bang.
"Ron, what happened?" asked Hermione whilst Ginny looked on in disgrace.
"The Exploding Potion...Well...Exploded," replied Harry.
"I was talking to Ron," she replied.
"I am-" Harry started until Ron hastily pulled him into a corner, away from anyone's earshot.
"Ouch! What the h-?" Exclaimed Harry before he looked at his companion and saw
his own body facing him instead.
"What the bloody hell just happened?" Harry whispered in panic; however he didn't need an answer. The potion had gone wrong and they had switched bodies; Harry was in Ron's body and vice versa. Looking over to the girls, Harry (in Ron's body) asked his friend,
"Do you think we should tell them?" to which Ron (in Harry's body that is,) slyly replied,
"No...Let's have some fun." Amongst the confusion, Professor Drover had been getting even angrier; unaware of the calamity that had occurred she shouted,
"Weasley, Potter, Granger, Weasley…again…come here!" The four walked over meekly. "You all have detention everyday after school for the rest of the week! Now," she pointed a thin finger at the four friends, "go and get cleaned up this instant!" The four did as they were told and went up to their dormitories, to have their showers. When they had freshened up, they returned back downstairs to Professor Drover as to start their detentions.
Upon arriving, Ginny went and sat next to who she thought was Harry, but in fact, was her brother Ron; Hermione, seeing this, joined who she thought was Ron. The two were not dating though everybody knew that they liked each other, they weren't very discreet in hiding their feelings. Hermione, being the more mature of the two, decided to be brave and ask Ron out, in fact, she was going to ask him right now!
"Ron," Ron, still in Harry's body turned his head but realised that she was addressing Harry and turned back to Ginny, though he kept an ear on the conversation.
"I think…would you like to…do you want to go to Hogesmede this weekend?" She stumbled frequently through her sentence, a trait which Ron found extremely cute, "with me, I mean, like...a…a date?"
