"Albus, you are the love of my life and I want to spend the rest of my life with you."
Scorpius dropped to one knee, and asked: "Albus Severus Potter, will you do me the honor of marrying me?"
The shock was on Albus' face.
"But Scorpius, the the wizard law does not recognize gay marriage. "
"No, but marriages performed under muggle law — generally between a muggle and a wix — are automatically recognized by the wizard law. If we send them a muggle marriage certificate then they will have no choice but recognize our union. "
"You have found a legal limbo that we would be officially recognized as a husbands? "
"Yeah, so Albus, will you marry me with the muggle way? "
"That's the most meaningful proposal! Of course I want to marry you! "
Albus kissed his boyfriend, no his fiancé, then their kiss intensified and they went to the bedroom to celebrate their engagement.
OoOoOo
Albus was in his thoughts, happy, cuddling with the man of his life.
"Scorpius?"
"Hmm?"
"Can you imagine the reaction of your grandparents when they will find out that you are getting married at a muggle city hall?"
Scorpius giggled at that idea. "A gay grandson and marrying with the muggle way. Grandfather is going to have a heart attack. But only the civil ceremony would be muggle, then we can rent a wedding hall and celebrate our union in wizarding way."
OoOoOo
Some might say that Scorpius and Albus were the driving force behind the legalization of same-sex marriage between wizards and witches. They were the first to use this legal limbo to have their marriage recognized by the wizard law and many followed. For a time, they feared that a new homophobic law results from their plot. Maybe they weren't the first to use this legal ploy, but they were the first to get publicity about it, which was enough to trigger changes in wizarding society.