Jaha and Junghwa grew up together as children.
They were both part of the seven great families, and both wanted to cut ties with the pressure and expectations that came with being heirs of said families. Unlike Junghwa, who was ambitious and had goals to change his situation, Jaha was apathetic to everything and was more than willing to accept everything if it meant blending in and avoiding troublesome things.
His views, however, changed after meeting the young Demon Lord. Having a kid two years younger than him climb the ranks with so much skill and talent sparked a change in him. And so, he decided instead of living his life of apathy, he'd stay by Junghwa's side and see his plans through. He was there to witness it all. All of Junghwa's strengths and weaknesses. All the sacrifices he had to make and the pain he had to endure after witnessing his closest friend's betrayal. It broke him and left him with permanent scars. The last thing he wanted was a repeat of that.