[He honestly wishes he could just... not care. Just this once, when so many of his other cares have been shoved aside. It's not like they need to keep speaking and if he doesn't say anything to Asura he can continue doing what he is doing, the blood wouldn't do anything unless Booker said something to trigger it. Logically, he's aware of this.

But it's reflexive, really, as soon as a scrape of teeth errs on the side of too rough he jerks away, shoving on Geto's throat to push him back against the wall and pulling back himself to catch his own breath.]

Do not get my blood in your mouth.

[He pulls his hand away from Curtain's side to rub it against his own mouth, making sure he caught it before he bled, and loosens the grip on Asura's throat so he can catch his breath too.]