He gasps -- or whatever it is when your reaction is to gasp but there's just no air coming, the beginning of something that's characterized not so much by what it was going to be but by the brutality with which it was cut off -- as the whip pulls tight around his throat, fingers digging into his own pants legs to prevent any reflexive flailing. 'Guess I was hittin' a sore spot there! Sorry, man!' or 'Chill out, man, or somebody'll think you got somethin' on your mind' or 'Play nice, Kaito, 'cuz the only rules you got here are the ones I'm lettin' you have' are things that Sora might have said, were he able to speak. That clearly not being possible, what with him not being able to even breathe, he settles for a thumbs-up of the 'gotcha, boss' variety.