Maybe Spike has accidentally been eating saltpeter. Just saying, he doesn't exactly pay close attention to what he's shoving in his gob, so there is a distinct possibility that's been happening.

Molotov very obviously does not believe this, but just sits back with a shrug, lighting up a cigarette of her own. "Whatever you want." Her tone is blasé, but he has clearly offended her.

Why even bother being nice?