What does the 'role play' consists of at Co op bank interviews?

Just what is says, really.
They will ask you to "act" in a scenario. For instance, you might have to be a staff member who is confronted by a pretend irate customer.
Or, you might have to be a staff member dealing with an old person who doesn't know how to transfer money.
You wont have to know the way the bank operates, all they want to see is how you cope with those sort of situations.
Good Luck