Jae-Kyu Kwon

He is the second-in-command of the Sun-Woo Clan, Head of the Elder Council of the Sun-Woo Clan and grandfather of Jin-Ie Kwon. He is extremely dedicated and loyal to the Sun-Woo Clan. Elder Kwon gave up the opportunity to form his own clan even after the Sun-Woo Clan's ruin and chose to stay with the clan. He regards anything that could be a danger to the clan as a threat which must be eliminated. Despite being seemingly arrogant, he is also extremely perceptive as he could identify that So-Jung Chan was attempting to corner the Sun-Woo Clan by asking about their new Ganju as Shi-Woon, and attempted to silence him immediately.

(Source: Wikia)