[Wow. Okay. Yeah that seems to disgust him but if Spike is as perceptive as he thinks he is he might know better. Sam is a man after all, a dog in a few different ways, he'd be lying if he hadn't thought of it or didn't want her.]
Wh-What!? No. It's not like that.
I protect the people I care about. An' that's all there is to it.