...affection? or are they just tasting what you had last night?

Depends ware you let them lick you

Yes they really like you. They can't exactly hug you can they?

They are trying to get the taste of butt off their tongue..

Dog's do lick for telling you they love you, but they also lick to get the salt off of your body. Yahoo a free bath

Dogs lick you because they love you a lot. Also, they do it so that you "smell" like them. Thats a dog's way of telling other dogs that you are "their" person. Ever notice, if youve been playing with another dog or something, your own dog will sniff you all over really crazy and then lick you nice and proper to get his own scent onto you. And if youve been away for a few days, and you get licked, it smells a bit different than when you get licked normally. Dogs dont like it when you have a bath and use soap and stuff, because it wipes off their scent and they have to lick you all over again to put it back on.