[Zero actually laughs. A sort of cold and bitter laugh but one none the less.] Yuuki is trying to make a deal that will have her turned into a vampire.
Get out of the way! Why--
This woman is the only one that can save you, Zero!
[Which, for all the trauma and stress this had caused him--this aspect seemed almost funny today. Just not quite yet. He wasn't that well healed from anything that had happened that year to find this ironic in an amusing way. Maybe in 200 years or so...]