I would go with "Court Nonce", you know like they used to have a Court Jester, or Court Dwarf if you are familiar with Crusader Kings.
While I abhor Andrew and would like to see him come right unstuck in the New York court case, unless I’ve missed something the youngest person that he’s alleged to have had sexual relations with was 17.
While that could certainly be described as morally wrong for a man of his age at that time, it is far removed from making him a nonce.
Court Ephebophile doesn’t exactly roll off the tongue, but it’s closer to the truth than Court Nonce.
According to the Urban dictionary, a nonce is U.K. slang for a paedophile.
Paedophilia is a psychiatric disorder in which an adult experiences a sexual attraction to pre-pubescent children, girls up to age 10 or 11 and boys up to 11 or 12.
I reiterate, I have no time for Andrew, but 17, while dangerous ground, is quite a bit older than 11 or 12.