TW

Y/N and Mattheo Riddle had been together for a year, and from the outside, their relationship looked completely normal. They were the kind of couple everyone had gotten used to seeing together, whether they were arguing over something stupid, sitting beside each other at parties, or disappearing for hours because neither of them could stand being around everyone else for too long. They knew each other's habits, moods, routines, and little tells well enough to notice when something was wrong. It was almost ironic, then, that neither of them had noticed what was happening right under their noses.