Zaki was slept on the bed at the corner of Sei's study room. Well, to him, it was too much of a hassle to go back to his own room so he just preferred to sleep there. And more importantly, this place was the closest towards the couple's bedroom, making it easier for him to access if in case something unthinkable happens.
That moment, his sharp as ever senses already felt that someone was coming, causing him to immediately open his eyes. His line of sight fell to the wall clock and its still three AM.
He didn't move at all. He just covered his eyes with the back of his hand as he waits for the door to open. Of course, the reason was because he knew that it was Sei who's coming.