[He's very salty for someone who physically cannot handle salt water.]

... Fine, I'll grant you that.
[Like... it's not a great argument as far as establishing her good intentions, but it's logicially valid and Law can respect that. He still wants info, though. Because he's a rude man who doesn't have any concern for a girl's feelings.]

You said you can eat food normally as well as drinking blood. Is that something that can be substituted entirely or do you need some amount of blood to survive?
[He's hoping it's the latter because then there's Scientific Questions that need to be asked about what's so special about blood that can't be obtained just by eating meat. Are vampires just super anemic by default and need large amounts of iron? Who knows.]