Madison was in a bad mood that evening. Things had not gone according to how she wanted it to and she had been given a detention for something she had done. Most would have seen this as something fair - being punished because you broke a rule - but not Maddie. To her, it was an inconvenience, and annoying, because it meant she failed to convince the Prefect that she didn't deserve it.
So, naturally, Madison spent the hour in the detention hall plotting the accidental downfall of said prefect. Nobody came against her and didn't get some sort of retaliation, unless they were vastly more powerful than her - and, currently, she saw nobody that filled that position.
Slipping into her common room after having been let out a few minutes earlier by the sympathetic teacher on duty who had been on the receiving end of some of her famous crocodile tears and a story about how fair the detention was and how she had "learned her lesson and was so very sorry". Already she could tell the seeds of doubt had been planted in said teacher's mind of her guilt, and that was phase one done.
Being in such a bad mood, the moment Madison caught sight of the younger boy on the chair, her attention turned to him. There was nothing like toying with someone to make herself feel better. A fake smile playing on her features, she moved towards him. "Hi, mind if I join you?" she asked. "Tristan, right?" she added a moment later. They had never formally met, but she made it a point to learn the names of people in her house as well as potential targets elsewhere. It made things so much easier when and if she decided that they were to be a game, of whatever sort.