Royalty

so the peado wing inmates.

Interestingly it wasn't a paedophile specific term when it was first used. Men who were violent towards women or children and also murderers where it was perceived that the victim "didn't deserve it" were also N.O.N.C.E. I.e if other inmates didn't think that your crime was "honourable".

I'd be interested to know whether at this point in history, if a man went to prison for beating a woman, whether he would be deemed as needing protection from other inmates in the way he would have been a few decades ago. I am sceptical.

didn’t realise nonce comes from

not
on
normal
communal
exercise

Isn't that one of those ridiculous backronyms?

not
on
normal
communal
exercise

I’d like to see a citation with evidence for that origin. It looks like a folk backronym to me, akin to alleging “posh” is derived from port out, starboard home. The OED says (use your library card number to log in):

Origin: Of unknown origin.
Etymology: Origin unknown. Perhaps related to nance n. (see quot. 1984), or perhaps compare English regional nonse good-for-nothing fellow, recorded in Eng. Dial. Dict. Suppl. from Lincolnshire
[…]
1984 Police Rev. 18 May 975/3 Nonce, prison term for a child molester. The very bottom of the prison pecking order, the ‘nonce’ is usually segregated from ordinary prisoners at all times for his own protection. Originally derived from ‘nancy-boy’.