My question involves a child custody case from the State of: Illinois

The man I am dating is going through a divorce. They signed the papers today and he told me there was a standard clause in the IL paperwork that says neither parent can have someone of the opposite sex stay overnight while the kids are present. This does not make sense to me. He has physical custody, they have joint custody. I have been an active part of these kids' live for the last 8 years. I sleep on the couch and we have always been very careful. The kids are 15 and 16. Does anyone know anything about this or is he interpreting the paperwork wrong?