Naturally, if you have not read this Webtoon, my comment may have spoilers, I am talking about its up to date translated chapters. Soooooo......
I don't know why, but with these flashbacks, I find myself not liking Edermask all that much.
He seems weak.
Although his brother has a bit to much bloodlust, he had good intentions. Edermask sought peace, yes, but he failed in his pursuit because of his high ideals. Janus saw the ugly and it changed him. Edermask unable to understand, saw only his brother's anger, not thinking maybe Janus had every right to be angry. I'm just saying, Edermask kind of left Janus hanging, defying him for his own ideal which never worked out. Instead, they should have compromised, before they fell to far apart. Plus, letting a girl get between family... I'm just saying it could have been handled better.
He just seems to run away, even in current times. He just up and disappeared, leaving Enzu and Iremi to find their own way, after leading them into a life filled with so much danger. They were still children gosh darn it! I guess the best word to describe him, in my opinion, is selfish. Granted, Janus is just as selfish, though I feel Edermask has been so for far longer. He just didn't have the drive, passion, or fighting spirit Janus did. Which, I suppose is a good thing, considering how Janus is a Sociopathic, Evil, Douchebag.