Who put this stuff in my room? [Event related]

[lakesyaknow]

After wandering for a while Sven has finally found his room, or at least, he's pretty sure its his room. Most of these things are his, and he happily tidies it up. But some of the items in his room are a little unfamiliar. He picks up a pair of jeans and holds them up to his waist, giving them an odd look. "Who the heck left these clothes in my room?" he wondered out loud, also glancing at some kid's reading books on his shelf. While he was at it he also found some rather embarrassing things in his night stand.
He scratched his head and decided to occupy himself from these weird items by cleaning the room a little more.