Seth was in a bad car accident and is now in a coma. Dean decides to write to Seth in a notebook telling him about how they fell in love in case Seth wakes up and doesn't remember.
All in Dean's POV unless I say otherwise.
When Dean gets a car accident he ends up in the hospital. At first this is the most shitty thing that can happen, but after some time he finds out that the trainee is a really cute guy ;)