Sweaty, wet, stinky feet need to be cleaned and refreshed and when you have a slave tied to a bed, there's no better way to do that than to thrust them deep into his mouth! Lying there helpless, he also serves as a good stress toy, to alleviate the pent up frustration of the working day. Hearing him moan and groan in agony is somehow therapeutic... the more he moans, the better Mistress Suki feels, but there is a limit, so when his whining gets too much, she sits firmly over his face with a very effective smother muffle.