Disclaimer: I do not own Supernatural or 13 Reasons Why.

Two weeks.

It had been two weeks since Castiel took an angel blade to his throat and ended his own life. And for Dean Winchester, it had been the most painful two weeks of his life.

He still didn't understand why Cas had done it. When he found the angel's body, in Dean's own yard with scorched wing marks on the ground, Dean originally thought Cas had been attacked and didn't win. Then he saw the note.

I'm sorry, Dean.

He could almost hear Castiel's voice ringing through his head every time he read that note. And he read it and reread him several times a day, searching for something, anything, to explain why Cas did this. As if he expected new words to appear each time he unfolded the note.

I'm sorry, Dean.You're sorry, but you haven't explained why.

Dean swallowed the last of his beer before heading to his room to turn in for the night. Sam had gone to bed an hour ago. His brother had been acting weird all week. Dean wasn't entirely sure what his problem was, but Sam jumped and took on an expression like that of a deer caught in headlights every time Dean mentioned Cas.

Dean walked into his room and closed the door. He was about to turn out the light when he noticed a package sitting on his bed.

It was a shoebox. He opened it cautiously, and inside he found seven cassette tapes. Six of them had a number drawn on each side in blue Sharpie. The last one had a number 13 drawn on one side, with the other side blank.

"What the hell?" he muttered to himself.

He figured Sam must have left them, although he couldn't figure out why. Curiously, Dean took the first tape out, the one with the drawn numbers of 1 and 2.

Dean didn't have a cassette player in his room, but there was one in his car. He dropped the cassette back in the box. He was curious about what these were. Very curious. He picked up the box and headed outside to his car.

He left his door open as he climbed in and turned on the engine. He opened the shoebox and once again pulled out the first tape. He slid it in and waited for it to start playing.

Nothing could have prepared him for what he heard next.