Author's note: This was written for a tumblr prompt - a pairing, and AU setting, and three sentences. Oleander's One set the challenge of Sand and Safiya at Hogwarts.
They had been inseparable in their years at Hogwarts, and very similar, save that Safiya was tall and golden-skinned where Sand was small and skinny: with matching passions for Transfiguration, both of them bookish even by Ravenclaw standards, they had both won scholarships for further study after graduation… but Safiya had chosen the Thaymont Academy, while Sand had accepted his offer from the Hosttower, and in the rigours of their studies, they'd gradually fallen out of touch.
Sand hadn't known that the Hosttower placed such an emphasis on the Dark Arts, nor the loyalty demanded of its students, and the day he'd realised it was little more than a recruiting ground for Death Eaters he fled, then went into hiding as a purveyor of dubious philtres in Diagon Alley; while Safiya had earned a teaching position at the Thaymont Academy and enjoyed it immensely until another teacher had overthrown it in the Dark Lord's name, and in the search for its founder, who was said to possess the Philosopher's Stone.
So it was perhaps inevitable that when Dumbledore advertised an opening on the Hogwarts staff, after the war, both of them applied for it; that when they saw each other in the waiting room (Sand had grown his hair long, Safiya had shaved hers off entirely, in the Thaymont style) they should exclaim and smile and exchange stories and completely ignore the wizard in the purple turban, and that they should go for a butterbeer afterwards, which turned into a date and an amicable wrangling over Azzimauf's Constant – which Safiya won, nearly a year later, in the middle of their wedding ceremony.