K2 Blackpearl roles differentiation?

Depending on what you are trying to do, there are several ways to do this:

1.  If your AD is populated with organization information, you can route a task to the manager of a given user

2.  You could create a role called 'Managers' that contains all of the users who are managers

3.  You could create a SmartObject that contains information about your users and organizational structure, then use the SmartObject in a destination rule. For example, let's say you have a SO that has a definition like this:  UserID, Dept, ManagerFlag.  You could use this SO as a destination and specify criteria based on other process and activity variables so you could select the UserID who is a manager of the Accounting department.

There are probably even more variations depending on what you are trying to do. 

Thanks David!
The SO idea is a great one but unfortunately cannot be used in my case! :(

Does K2 have some kind of built-in manager role by any chance? If so, how would I be able to check in the tables for example to determine if that person is set to a Manager role?

Thanks again!! 

K2 does not have any built in manager. 

Why not use option #2 as stated by David?:

    2.  You could create a role called 'Managers' that contains all of the users who are managers

Yes, there is a built-in concept of roles.  You can define your own roles and the members of those roles.