I couldn't give a flying monkey's arsehole

You don't care enough to even look at the monkey’s butt, let alone fly with it.

My friend told me about his weird dream. I said, 'I couldn't give a flying monkey's arsehole.'

My dad asked me about my grades. I said, 'I couldn't give a flying monkey's arsehole.'

My neighbor yelled at me for mowing the lawn wrong. I said, 'I couldn't give a flying monkey's arsehole.'