Hmmm. This one is hard.
All I can think of is like, a cops and robbers AU in which Dean’s a criminal and either Cas or Victor is a cop who catches him. Little does Victor/Cas know that Dean is actually a crucial witness in a case against the biggest crime ring in town and throwing him behind bars is not an option. Now, Dean and his cop buddy must take down the crime ring and Cas/Victor must figure out how not to fall for the wise cracking con.