Christian had never received a letter from Blaise at school. Not once in seven years. Usually, the owl would fly up to Apollo and he would relay any information necessary to the younger brother. Daphne, of course, would send letters to both, but more frequently to Christian as if it would make up for the ones he missed. The twins weren't typically ones to seek each other out during the day, if only because they had classes together and could explain whatever they needed to during that time. But now, for the first time, he had news from Blaise that he needed to give to Apollo.
The Slytherin had not been down in the greenhouses, nor in his typical part of the grounds for studying. So Christian made his way inside and checked in on the library, wandering around until he decided that his brother simply was not in there. Finally, he decided to make his way down to the dungeons and towards the Potions classroom. He hesitated for a breath, wondering if it was strange that he knew precisely where to search, but then he decided that it wasn't so strange because he assumed Apollo would know the same things about him. He was wrong, of course, but he couldn't have known that.
Similarly, he couldn't have known that his only slightly-older brother would not be in the classroom when he opened the door and stepped inside to take a look around. Instead, he found a Slytherin from his year working on something. He recognized her, of course, if only from classes. But they had not really interacted enough for him to just strike up a conversation with her.
Then again, he had someone he was looking for, and perhaps she would know. So he approached slowly, not wanting to offend in any way - he knew how protective Apollo could be about his potions work. "Hey," he began, completely aware of how uncomfortable he appeared to be. "You haven't seen Apollo, have you? Been searching for him."
After another glance towards her cauldron, though, his curiosity got the better of him. "Um, what are you working on?" Surely Apollo would be curious to know if another student shared his appreciation for working on potions in their spare time? That what he thought his excuse was, anyway. A part of him knew that she had not exactly been the most friendly person in the world - at least, not towards him that he could recall - but he couldn't help but wonder after people like that. From experience, he had found that people who pushed everyone away had something that they were covering up, or had a silent wish that someone would address it and help them out of whatever it was.