Yuno was always observing him.
They were in the same classroom, but he sat on the back. Nevertheless, she always found herself staring at him when she got the chance, getting a glimpse of the boy that had won her heart without even trying, the one who had saved her when she was lost.
She needed him. She loved him. He was her saviour, yet he didn't know that either. Yuno felt as if her life was ending, as if there was no need for her to continue living. Her mother assured her that, she couldn't even acomplish the most simple tasks, and she got her mad. When Mom got angry, it was horrible. And Dad was never home to stop her.
Yuno remembers the cold cage her mother locked her in when she misbehaved. Sometimes she didn't even feed her. She thought that maybe, one day, father would rescue her, and things would be fine again. But that day never came, and instead, she was forced to rescue herself.
Now, her parents were gone, and Yuno didn't see why she should keep living. Until Yuki came into the picture. He had given her a reason to live, he had told her that they might get married one day, and that they would go to see the stars together. That was the only thing Yuno wanted in the future; to be with Yuki, with the boy that had given her something to keep living for.
Even if she had to kill everyone in the way.