He wasn't feeling well. He couldn't quite figure out if it was from drinking too much at the Slytherin party the night before or smoking too much weed, but he felt absolutely terrible. Of course, he didn't let his friends know about it. He would tough it out, like the man he believed himself to be. Well, at least half of it.
For half of the day, his plan seemed to work. However, studying magic became increasingly difficult. He couldn't concentrate to save his life, and while he didn't exactly despise it, he just wanted the nagging feeling to go away. That's how he ended up in your dorm room, skipping class while you were in your free period. He didn't bother to knock, simply storming in and flopping down on your bed, groaning complaints from his lips that had a rosy tint.
"God," he huffed, rubbing his forehead with his palm, now attempting to feign a fever. "I don't feel so good . . . I think I'm gonna throw up. . ." It was all just jokes, or at least, that's what you hoped.