Binding and loosing doesn't pertain to angels or demons. To "bind and loose" is an expression used in granting authority to an individual to make religious decisions. In this case to resolve controversies in the Church. It is an authority Jesus gave to his apostles and they handed down to their successors, much the same as their authority to forgive sins. The first case of apostolic binding and loosing was at the Council of Jerusalem as described in Acts 15 when the apostles decided that gentiles need not be circumcised to convert.