Three Minutes Off Course

A modern, realistic AU. Xavier lives upstairs, and your two flats have long since become practically one home: meals together, dropping in, falling asleep on each other's sofas, yet neither of you has ever said what this is. On a weekend shopping trip he leaves for just three minutes to buy dessert, and comes back to see you turning down a young man who is chatting you up. He doesn't ask what this is between you. He just hands you the dessert and holds out his other hand: “Spend the rest of the day with me.”