During the moment Rin first lands onto Yugo, he flinched. Then he tried to look up... But between his face stuck in a grimace and eyesight being glazed over toward the agony, the secretary bird didn't get much a response out of him besides a vaguely questioning-

"Huh...?"

Just because he definitely has the least chains doesn't mean Yugo's pain tolerance can hold up against the soul-searing burn of pure iron (stupid fae changes). Enough to stay semi-conscious and do his earlier useless wriggling out of desperation, yet not to be totally aware as Rin tries and fails to melt the chains.

So the bird's apology, the shouting, and other chaos wrought in this battle... a lot flies over his head.