The 2nd summer after the Battle of Hogwarts; Hermione, Ron, Harry, Pansy, Blaise and Draco are going back to Hogwarts for their 8th year, while Luna and Ginny are going for their 7th year. Molly Weasly is LGBTQ+phobic.
Hermione and Ginny went back to Hogwarts for eighth year while Harry and Ron did not. 21 years later, Hermione and Ginny have disappeared off the face of the earth, only to return to the 21st anniversary of the Battle of Hogwarts. And not alone, they have mysterious husbands and 8 kids in total.
Disclaimer: I own nothing but the plot. J.K. Rowling owns the rest.