[ It's the times when you don't want the cat to sit in your lap that she'll make herself comfortable, or something to that effect. It does help that Jack isn't pushing for it, that he gets to take him by surprise at least a little bit. Spike is shorter and lighter and this is unknown territory to him to some degree still, getting the upper hand in any sort of way helps. Not to mention, dangling this in front of Jack gives him more of a kick than he anticipated. It feels good to withhold. It feels good to be desired.
The taste of blood makes him growl deep in his throat, feral yellow eyes narrow and teetering on the edge of control. He's got it, Spike has an iron will when he needs to but damn if it doesn't feel good to let go a little bit, even with the soul. It's play, not murder. Jack can take it. Licking at Jack's busted lip, he coaxes him further back to lie against the pool table rather than balance awkwardly on the edge. ]