AN

Y/N and Mattheo Riddle have hated each other since second year at Hogwarts. Or at least, that’s what everyone believes. Twenty-five years old, living in separate flats, working proper jobs and supposedly acting like responsible adults, neither of them has quite managed to move on from the other. When their old friend group reunites for their monthly gathering at Pansy’s flat, Y/N expects the usual: too much alcohol, old arguments, and Mattheo Riddle being a complete pain in the arse. She does not expect him to arrive with a new girlfriend. Suddenly, years of unresolved tension become impossible to ignore. The girlfriend is sweet. Mattheo is smug. Y/N is completely, absolutely, definitely not jealous. And Mattheo? Well. He’s never been particularly good at hiding anything from her.