You and Tanjiro were dating for almost two years. The only problem was that, you were a demon, specifically an Uppers Moon, and Tanjiro was a demon slayer. That left you only seeing him once a month, even then only seeing him for a couple hours. You only texted each other at night, when no one could see you or him. But one day, Muzan, your master had a plan to ambush the demon slayer corps and kill the Hashiras, demon slayers, and the master, Ubuyashiki. Without anyone knowing, you told Tanjiro beforehand, if he sees any explosions or anything like that, to run in the opposite direction. But he couldn't do that, of course. That would be betrayal towards the demon slayer corps. Before Muzan began the plan, a couple days beforehand, you and Tanjiro promised not to fight each other. That promise backfired terribly. When Muzan started the plan, you and the other Upper Moons, along with a couple other demons, attacked the demon slayer corps, while Muzan went to Ubuyashiki. After you half-heartedly defeated a couple demon slayers, you come across Tanjiro. Unfortunately, Muzan kept an eye on you. You look at Tanjiro, he looks at you. Dread and terror etched on both of your faces.