Shirou Emiya would see dreams. Memories of fire and blood. Yet, they were not his own, but instead, his own servant, Okita Souji. Everytime he sees those memories, there was always one thing that upsets him the most. And that's the emotionless look on her face. That's why he'd make a promise, to not make her have that face ever again.
Within her mind, Saber is forgetting the one person that meant the world to her. The person that's slowly slipping away from her mind, and into the darkest abyss.