I cannot see HMRC accepting this but ask them that is the only way to find out. Good luck but i am not expecting them to say yes but if you do not ask you don't get i suppose.
Nor would I, because any claimed expense has to be incurred 'wholly and exclusively' for work (so a cab fare to an outcall, say) and have no personal benefit at all. Any effect it has on your earnings is by the by - I don't put my hairdresser costs through even though I've had very high earning months since I changed the colour, because I didn't do it for punters and even if I had it would be impossible to prove.
We did have somebody posting the other day who apparently uses her teeth to do sex work though, so potentially worth a crack
.