Both are about investigating crimes but ghost is more cyber related and they're solving one crime.
A second season of Vampire Prosecutor, recommend you start with the first. The vamp is a prosecutor who uses his vamp abilities to help him solve crimes. There is a lot of bromance between him and the police detective on his team and a hint of romance with his junior prosecutor. In addition to the Crime of the Week, he's busy tracking down the big bad. It has a similar type of humor as Vampire Detective.
