Ianto can't bite back a faint yelp as Spike's hand connects with the bruises he knows perfectly well are there. It's not enough to distract from all the innuendo flying around of course and he bites back a smile that would ruin his annoyed expression.
"Thrash away, sir," He replies in that best Torchwood butler tone, the one that is flirtation hidden behind just the right amount of politeness.