Green’s Dictionary of Slang

arva n.

also harva

(Polari) sex; thus ‘the full harva’, anal intercourse.

2019		P. Baker Fabulosa 288/2: (the) arva, harva, sex. Also ‘the full harva’ (anal sex).
2023		R. Milward Man-Eating Typewriter 111: [O]utright grubby arva-hunger.