Bang Yong Shin isn't the one who shoots the gun in the head, or the one who stabs the knife in the chest. She is the mastermind. She is very organized and strategic, to the point of which she can be scary. She can use and manipulate anyone and anything as part of her plan. Like the Silent but Deadly, she is cold and merciless, but like the Monster, she won't hesitate to knock down anything and everything that stands in her way.
But she barely need to do that, no, because she so carefully plan and work her way around major threats, almost always resulting in the desired target(s) dead. Assassins are like pawns in a chess game to her, she must strategically place them and think out her every move, until she can knock down the king. However, if someone were to outsmart her, she quickly become consumed with rage, and her plan can crumbles to pieces.
She is the most deadly and fearsome out of the assassins. she love to watch people get scared, or suffer, or just in sheer pain. The ear piercing screams and shrieks from her victims are like music to her ears. She take pleasure in seeing people beg for mercy at your feet. She use a variety of weapons, but she prefer the ones that cause the most pain.
From the outside, she look like a civilized person, perhaps even approachable. But on the inside, she have a thirst for suffering and blood from others. She are the farthest from an assassin, but rather a murderer who goes about it in the worst, most feared possible way.