[Well, Spike could get used to this treatment. Even if he was waiting to see what he'd have to do in exchange. It has also not escaped him at all the way the other's attention focuses on the mug. No blinking, a facial tic.

Oh yes, the other is hungry. As it is he takes the mug and let's himself sniff it. Savoring that wonderful life-giving scent. He very much appreciated NOT being hungry.]

No clue, but I'm pretty sure it's mostly mammalian at least. I can live off of it, as it were. Can't do that unless it's a mammal's blood.