[It's not a pleasant thought, and he wonders if it's worth pointing out that Jack at least isn't likely to hold it against him. After all Jack isn't really the point. The fact that this could so easily happen to anyone else is what's more worrying now. And yes, he's always more than a little blinded by love and optimistic where Spike is concerned but even he knows everyone here is in danger until they figure out what caused this or how to stop it. He imagines for a vampire it must be harder to ignore the craving for fresh blood once you've had a taste.]
I'll do everything I can to keep you from hurting anyone else here. [Once that would have been a threat, now it's a promise of support. Funny how things change.]