He wants to protest the doing anything for him, he really does. But right now he can't because if he can get Inigo to see a doctor and have basic modern medical care before the warrior has to return, he'll just have to grit his teeth and deal with it. So Yuki can't get into the real reason even if he wants to. He's more than sure he'll get a slapstick brush off of 'Eh I'm fine, who needs that stuff?!' in response and then they might have a real problem.

So the why though question has him torn and he can't answer without lying. "Nevermind..it's okay if you don't want to." The silvery head goes down because he can't lie to Inigo. And the truth would only cause a fight. Weakly he smiles and tries his best to just let it go.

"Don't worry about it, I'm sure..you'll be fine, right?" Yuki keeps the smile up just for a moment before shaking his head and a more serious expression shows. "I'm going to go..you enjoy the rest of the party."