Spike looked down at his skin, which had a faint glow to it with the amount of electricity Xander had pumped into and around him. It was the only reason why he’d left when Xander said so. Xander had been so busy trying to protect Spike that it could lead himself to harm. Without Spike present, Xander could concentrate on protecting himself.
But Spike hadn’t gone far. He had circled around until he was behind the foursome, within sight and hearing of what was going on but far enough away that he wouldn’t be noticed. He wouldn’t leave Xander when the boy was in a dangerous situation. Call it the curse, loyalty, or the truth: he truly cared about Xander.
Spike had discovered this tidbit when they’d stopped over at Angel’s in L.A. Angel had offered Spike the opportunity to stay and, as tempting as it was, there was too much baggage there and he could never fully trust Angel. The moment the soul took a walk, Spike would be in a world of hurt, physically and emotionally. Spike would never chance it.
Spike trusted Xander, as he’d said the night before, and to have it reciprocated was something precious and not to let go of, even for a soulless creature like himself.
The situation diffused at the campsite, with Willow’s phone call to Angel. Spike overheard the part about being enthralled and was surprised to hear Xander confirm it. It looked as though Xander wasn’t going to share everything with his friends. To know that Spike was the only one who knew everything made him puff up with importance.
He waited until Willow and Buffy started quizzing Xander on his powers, the atmosphere now relaxed, before he took his leave.