The Ballad of John Watson

John Watson was many things. An army doctor, a military man, his flat mate. His best friend.

But he'd also been someone before all that. Before the University of London. A talented musician. A poet.

He didn't write poetry anymore and Sherlock had no idea what he'd played. It was the mystery of John Watson. Although some days the mystery was more why he stayed.

OR: Jaskier world hops after the end of the books and becomes John Watson.