It was Aectaeon's first time to kill a human being.
That's why he couldn't get the image out of his head.
The sensation of stabbing flesh, he could still feel it in his hands.
The sound of Merlon croaking as he spitted blood, it was still ringing in his ears.
The glints on Merlon's irises slowly fading before he met death, Aectaeon could still see that very sight every time he closed his eyes.
However, he couldn't get over it not for the reason that his conscience was pricking him. If anything, the slightest of guilt wouldn't be found in his being.
It was because Aectaeon was yearning to encounter those sensations yet again. He was just suppressing his urge lest going out of control before he could even start discovering himself. Moreover, the very fact that their lives were nothing but insignificant within the Obelisk completely extinguished his morality regarding the lives of others.