While Zohakuten wakes up screaming in anger at simply existing in a world where weekends end, Merus simply doesn't give a damn and just moves in bed to remind Zohakuten that he's still there and that it is Sunday. Then the demon of hate stops screaming, mumbling why he didn't do that before, while Merus replies that he woke up ten seconds ago.
Zohakuten was indeed created from the emotions of an abusive husband, but he is not fucking insane enough to lay a finger or a slightly higher tone of voice on the Grand Priest's son.
This contributed a lot to him learning love XD