Draco Malfoy was pissed. His friends were complete idiots and he just had to get away from them. He left the Slytherin common room and wandered around a castle, enjoying his alone time. He turned a corner and found Granger and her boyfriend snogging like maniacs. He was about to turn around, disgusted, but then he saw Landon throw her to the ground.
He quickly hid behind a wall, silently witnessing everything. He watched that bastard leave her helpless on the ground. Draco wondered what everyone would think of Landon if they knew this interesting detail about him. Everyone thought he was so bloody perfect. He found himself admiring the mudblood's strength, not once did she cry out. Draco was suddenly infuriated. The abuse was nothing new to him. He had watched for years as his father beat his mother whenever something didn't go his way or he was just bored. Draco never had the courage to stand up to his father and defend her, so he would just walk away. He never saw any trace of abuse in the mornings, but he knew it was hidden just under the surface of all her concealment charms.
Draco was surprised at how much he wanted to help the mudblood. He knew deep down that no one, not even her, deserved to be treated that way. He wondered what would have happened if he hadn't been walking down that corridor. No one would have ever found out and she would always be stuck with him. Draco decided that he needed to help her, no matter what it took, he wanted to help someone who was abused to make up for what he couldn't do with his own father.
"Now" he thought, although for some reason, his legs wouldn't allow him to move. he felt like a coward. He watched as Granger weakly pulled her wand out of her pocket and waved it over her body, applying concealment charms. She shakily got up and started walking back to the Gryffindor common room, the opposite direction that Draco was standing. She never noticed he was there.