Yylfordt was doing his best to rally from the surprise. He hadn't taken this guy for a Ryoka; he just looked Al Bhed to Yylfordt. Sure, so he had Ice chakra, which was basically like finding a unicorn, but there were any number of ways that could have happened, including the fact that he's a scientist by his own admission. Khamja collecting an ice elemental Al Bhed scientist was exactly the sort of shit they'd do.

And instead, this was the fucker they hadn't been able to get past. He'd been there when Grimmjow had been hurt, and when Kadaj had taken down his boyfriend in response....

He scratched his head, awkwardly, and took a couple of unconscious steps back away from the Ryoka. Even Yylfordt knew he was winding Tayuya up, whether he meant to or not, and Yylfordt didn't fancy staying in the line of fire.

Literally, in Tayuya's case. The new dude might be stronger, but Tayuya could still hurt him if she wanted to.

Not that she should. Kuja'd be pissed, and less inclined to make excuses than her old boss might have been.