I do love the Brits and their use of Arse instead of Ass. The roundness of the sound of “arse” is more elegant than the nasal flatness of “ass.”
However based on the language used in this video, certainly “ass” would be entirely proper. This is
Nina Conti at The 2009 Melbourne International Comedy Festival Gala for Oxfam Australia.
Nina and her monkey perform an aria from Nessun Dorma… while she has her hand up the monkey’s arse.
If the aria sounds familiar, another Brit, Paul Potts used it to gain some fame and notoriety.