I generally refer to myself as “A Registered Sex Offender” because as you say I am not currently, or will ever be a sex offender again, but I am still a “Registered Sex Offender” or if that term doesn’t work for the situation I refer to myself as a “Registered Person” I don’t even like the term “Registered Citizen” because I feel that the term Registered negates the term Citizen so that becomes an oxymoron, but registered person is quickly becoming that same oxymoron.