Surely this is part of a cuck's duties. Prepping his hotwife before the bull arrives, ass and pussy, with his tongue or fingers, but not being permitted to make her cum, then after the bull arrives, fluffing him if he or the hotwife wishes it. His asshole should also be at the bull's disposal. Finally he should undertake cleanup duties, slurping the bullcum from his hotwife's pussy, then cleaning the bull's cock and balls with his tongue until they're gleaming!