Disclaimer: I do not own Teen Wolf or any of the characters.
When Stiles was five years old he had nightmares of the boy that hid under his bed - the Bogeyman, his dad had called him - that he insisted was real. He was. Stiles was sure of it, he'd saw the boy (who couldn't have been any older than him) under his bed once or twice and was convinced that the Bogeyman was coming to get him. Oddly enough, whenever his dad checked under the bed, the boy dissappeared from sight. When his dad left the room, the boy was back. Surely enough, it freaked Stiles out to no end.
When Stiles was ten years old he decided it was stupid to be afraid of his 'roommate'. They even occasionly talked when Derek - that's what Stiles had named him and he seemed to like it - was sure Stiles' dad had left the house. Derek didn't seem scary, he was more grumpy if anything. It was fun, Derek was his friend. He had Scott as a friend but recently Scott had began to like girls more than him and Stiles didn't like that very much. Derek didn't seem at all interested in girls and devoted his attention to Stiles. He liked that.
When Stiles was fifteen he started having dreams of an entirely different nature about the Bogeyman - Derek - coming to get him. Which was very awkward considering Derek literally lived under his bed. Stiles had to make numerous excuses for Derek to leave his room for a few hours so Stiles could pleasure himself to the thought of the man he was once scared off. Still kind of was. Stiles couldn't help but want to scream at the fact he was probably the only person that could fall for the monster under his bed.