Report on users that doesn't have read-only ITIL and ITIL role

[pavanakumar]

We have several assignment groups that grant the ITIL role, either directly or through inherited roles. I’m trying to build a report that identifies users who do not have either the ITIL or Read-only ITIL roles. Could someone please advise on which filters would be most effective for this use case?

[Ankur Bawiskar]

@pavanakumar 

what do you mean by Read-only ITIL?

which role is that? is that a custom one or an OOTB one?