Angel sometimes has pyoderma, im not saying it is that as it is quite hard to tell by a pic. Check around the folds near his mouth (sort of where the skinfolds over each other) his other "armpits" and the folds of the skin around the genitals and see if there is anything slightly similar.
I use a weak solution of hibiscrub, then rinse and dry thoroughly - i find it easier to use bounty (not the chocolate

) to dry it. just press a bit on rather than rubbing so as not to make it sore.
Sorry not much help! it could just be nettle rash!
Hope Bailey is looking better this morning
Sam and Angel