Well, first what was his offense? Is he a child molester or a rapist? You do know that you can become a registered sex offender by more then rape and child molestation right?
Chances are the manager already knows that the guy is a sex offender, but if you wish you can tell the manager.
If you are wondering why I seem a little picky about this it is because sex offenders are often labeled as child molesters even though they are not, and that they must be registerd their entire life. So their crime is a life sentence.
Whereas Murder, Assault, Drug sale, Robbery, DUI, DWI, drug possession and every other crime has their sentence and once it is served it is done. Sex offenders, no matter what their crime, must go door to door and let their neighbors know that they are sex offenders. While the drug dealer, murder, robber, etc don't.
I both agree with the sex offender registry and highly disagree with it. Why should someone have to have the stigma of a rapist when all they did was have consensual sex with someone but someone else didn't like it and said it was rape?