While he was furious at the sudden ambush, Kiro was also impressed that he didn't sense the enemy, not even when he was right behind him. He didn't let out any bloodlust, he only assumed he was just another customer in the room. The only thing that gave him away was the poison dart that he took out, which Kiro saw through vibrations.
The assassins of the Underworld were very outstanding in his eyes, he hoped they'd drop the skill so he could pass it on to Nikolai. That would make their group more overpowered and more likely to be hired as mercenaries. But he didn't put too much hopes in that, as much as he got a useless flute, nothing else he killed here dropped any items.
When he turned around, imitating the ones he entered with, he was greeted by another sight that he didn't quite like. Every being had their heads on the ground, showing respect and gratitude to the King that came back for them.