I remember there was a Daily Mail article at the time he left his wife, Pennox, in 2010, which talked of this.
It's been 'disappeared' now, and only a shadow of a hint of what was in it on Google search: '27 Aug 2010 — Crispin Blunt, the Tory MP and prisons minister, said there was nobody ... who hired the services of a rent boy - with his wife Belinda, ...'
Poor Belinda. She was devastated.
(God I loathe that term 'rent boy'. These were abused male children ffs. It's like calling the girls in Rotherham etc 'prostitutes' and 'madams'.)